There are 1.5625 grams of the radioactive substance that would remain after 60 seconds.
What is an exponent?The exponent of a number represents the total time required to multiply that number. 8 8 8 may be stated as 83 since 8 is multiplied by itself three times. In this case, 3 is the 'exponent' or 'power' that indicates how many times 8 is multiplied by itself, and 8 is the 'base' that represents the integer being multiplied.
The exponent is given as:
y = a (1 - r)ˣ
As per the question, we have
a = 100, and r = 0.50 and x = 6
Substitute the known values in the above formula, and we get
y = 100 × (1-0.50)⁶
y = 100 × (0.50)⁶
y = 100 × 0.015625
Apply the multiplication operation, a
y = 1.5625
So, after 60 seconds, 1.5625 grams of the radioactive substance would remain.
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one student we wrote the expression 17 * 102 as 17(100+2). then she simplified to get the expression 1700+34.
Answer:
Step-by-step explanation:
One student rewrote the expression 17 * 102 as 17(100 + 2). Then simplified to get the expression 1700 + 34.
a. Are the three expressions equivalent (17 * 102, 17(100 + 2), and 1700 + 34)?
Yes, they are.
Check your answer:
17 * 102 = 1734
17(100 + 2)
17(100) + 17 * 2
1700 + 34 = 1734
1700 + 34 = 1734
b. What property of numbers does this demonstrate?
This expression demonstrates the commutative and distributive properties of numbers.
Hope this helps!
PLS HELP WILL GIVE BRAINLIEST :)
Step-by-step explanation:
the slope intercept form is
y = ax + b
"a" being the slope, "b" being the y- intercept (which is the y-value when x = 0).
the slope here :
in the table x is always increasing by 2.
and y is always investing by 1.
so, the slope is 1/2
the y-intercept :
we need to find the y-value for x = 0.
but we don't have a data point with x = 0 in the table.
so, we have to extend the structure of the table to the left.
x decreases by 2 (making it 0), and y decreases by 1 (making it -1).
therefore, the y- intercept (b) is -1.
and the line equation is
y = (1/2)x - 1
not sure about "the other method".
there is the point-slope form of the equation :
y - y1 = a(x - x1)
again with "a" begin the slope, and (x1, y1) being a point on the line.
if we get the y-intercept in the table, then this point is (0, y1).
and the equation would be
y - y1 = ax
in our case
y + 1 = (1/2)x
and another method ?
sometimes people write
nx + my = c
in our case starting with the original equation
y = (1/2)x - 1
2y = x - 2
-x + 2y = -2
x - 2y = 2
HELP ASAP!!! ILL GIVE LOTS OF POINTS AND BRAINLIST
PLEASE SHOW HOW YOU GOT THE ANSWER!
Answer: 27
Step-by-step explanation:
A parabola can be represented by the equation y2 = –x. What are the coordinates of the focus and the equation of the directrix? focus: (negative one-fourth, 0); directrix: x = One-fourth focus: (one-fourth, 0); directrix: x = Negative one-fourth focus: (–4,0); directrix: x = 4 focus: (4,0); directrix: x = –4.
The focus and directrix of the parabola are (–0.25, 0) and x = 0.25. Then the correct option is A.
What is the parabola?It is the locus of a point that moves so that it is always the same distance from a non-movable point and a given line. The non-movable point is called focus and the non-movable line is called the directrix.
A parabola can be represented by the equation y² = – x.
The coordinates of the focus and the equation of the directrix will be given as
We know that the standard equation of the parabola y² = – 4ax.
On comparing, we have
a = 1/4 = 0.25
The focus of the parabola is at (–a, 0) that is (–0.25, 0).
The directrix of the parabola will be given as
y = a
x = 0.25
More about the parabola link is given below.
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Answer:
A. focus: (negative one-fourth, 0); directrix: x = One-fourth
Step-by-step explanation:
i did it
find inverse equation for y=(x-3)^2
Answer:Rewrite the cartesian equation as a polar equation.
Rewrite the cartesian equation as a polar equation.r
Rewrite the cartesian equation as a polar equation.r2
Rewrite the cartesian equation as a polar equation.r2cos
Rewrite the cartesian equation as a polar equation.r2cos2
Rewrite the cartesian equation as a polar equation.r2cos2(
Rewrite the cartesian equation as a polar equation.r2cos2(θ
Rewrite the cartesian equation as a polar equation.r2cos2(θ)
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6r
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−r
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(θ
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(θ)
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(θ)=
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(θ)=−
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(θ)=−9
Rewrite the cartesian equation as a polar equation.r2cos2(θ)−6rcos(θ)−rsin(θ)=−9Tap to view steps...
The quadratic function which is represented by the graph of a Parabola fails the Horizontal Line Test thus is not a one to one function. Therefore the inverse is not a function unless with restricted domain.
Edit: Adding the solution below to address update in the comments:
y
=
(
x
+
3
)
2
x
=
(
y
+
3
)
2
±
√
x
=
y
+
3
y
=
−
3
±
√
x
=> inverse relation
Restricting the domain: Recall that the domain and the range of the inverse function are the range and the domain of the original function respectively. The range of the original function in this case is
y
≥
0
, that should be the domain of the inverse function so for the inverse function we take the positive square root as follow:
f
−
1
(
x
)
=
−
3
+
√
x
=> this is the inverse function the domain and the range are:
domain:
x
≥
0
range:
y
≥
−
3
This means we need to restrict the domain of the original function to:
x
≥
−
3
in order for it to have an inverse function.
What is the trigonometric ratio for cosn? enter your answer, as a simplified fraction, in the boxes. $$ triangle l m n with right angle m. l m equals 15. l n equals 39. m n equals 36.
The trigonometric ratio will be Cos(n)=12/13
What will be the trigonometry ratio?Given is a Right triangle LMN with right angle at M i.e. angle M = 90 degrees.
Given are the sides LM = 15, MN = 36, and LN = 39.
It says to find cos(n) = ?
So opposite side would be LM, adjacent side would be MN, and LN is the hypotenuse.
We know that the cosine ratio is given by :-
[tex]Cos(n)=\dfrac{adjacent}{Hypotenuse}[/tex]
[tex]Cos(n)=\dfrac{MN}{LN}[/tex]
[tex]Cos(n)=\dfrac{36}{39}[/tex]
[tex]Cos(n)=\dfrac{12}{13}[/tex]
Hence the required ratio will be [tex]Cos(n)=\dfrac{12}{13}[/tex]
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Students in Ms. Seiko's class recorded the number of books they read over the summer.
books read
7 8 9 10 11 12 13 14 15
Mrs. Vitale's class is the same size as Ms. Seiko's class.
One fourth of the students in Mrs. Vitale's class read 11 books
How many students in Mrs. Vitale's class read 11 books? Enter your answer in the box
students
44 students in Mrs. Vitale's class read 11 books
Ratio and proportionsLet the number of students that read 11 books in Mrs. Vitale's class be x
If One fourth of the students in Mrs. Vitale's class read 11 books, then
1/4 x = 11 books
x = 11 * 4
x = 44
Hence 44 students in Mrs. Vitale's class read 11 books
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Answer:
Step-by-step explanation:
The total number of students that are plotted on the line plot is 20.
We are given that Mrs. Vitale's class is the same size as Ms. Seiko's class so both classes have 20 students in each.
One fourth of the students in Mrs. Vitale's class read 11 books.
1/4 *20/1 =5 students
Determine the value of k so that the relation {(2, 5), (k, 0), (–9, 2), (0, –9)} can be a function
Step-by-step explanation:
in a function every valid values of x has exactly one assigned y value.
in an ordered pair the first number is x, the second number is y.
the y in (k, 0) is therefore 0.
and this y is different to all other y values in the relation.
therefore, k must be different to all other defined x values (otherwise it would give an x value a second y value, which would make this a not-function).
so, k must be an integer not out of {-9, 0, 2}
If f(x) = 5x^5 + 1, then what is the remainder when f(x) is divided by x + 1?
Answer:
2l
Step-by-step explanation:
hence.f10 divido 8-2
The scale factor of a figure and its enlargement is 4. what is the new length of the enlarged figure if the original length is 4.5 cm? 4.0 cm 8.5 cm 16 cm 18 cm
The new length of the enlarged figure will 18 cm.
What is scale factor?A scale factor is a number which scales, or multiplies, the original figure by some quantity.
We have the equation for the scale factor.
Y=Cx
C is a scale factor for x. It is called the constant of proportionality or scale factor of y to x.
As the given length is 4.5 cm, so with a scale factor of 4, the length of the enlarged figure will be
[tex]Y=4.5\times4=18\ cm[/tex]
Therefore, the new length of the enlarged figure will 18 cm.
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The following double line graph represents the enrollment of students at Jefferson Middle School for 2006 through 2009. If enrollment continues in the same trend, which of the following is a good prediction for eighth grade enrollment in 2010?
130
200
165
75
Considering the double line graph, it is found that a good prediction for eighth grade enrollment in 2010 is of 165.
What does the graph state?It states that:
The number of students enrolled in the 7th grade is falling by about 20 students per year.The number of students enrolled in the 8th grade is increasing by about 20 students per year.In 2009, there were 150 students enrolled in the 8th grade, hence an estimate for 2010 should be of about 165 or 170 students.
More can be learned about graphs at https://brainly.com/question/24808124
Answer:
165
Step-by-step explanation:
What type of number is -91i?
Choose all answers that apply:
real
imaginary
complex
Answer:
complex
Step-by-step explanation:
Sharon is preparing for a trip to kuwait. she calculates that she will need $1,166 to be converted to kuwaiti dinar. if the exchange rate of us dollars to kuwaiti dinar is 1:0.2879, how many dinar does sharon have? round your answer to two decimal places. a. 335.69 dinar b. 405.00 dinar c. 3,356.91 dinar d. 4,050.02 dinar
Answer:
335.69
Step-by-step explanation:
If the exchange rate of USD to Kuwaiti Dinar is 0.2879, multiply the amount of USD by the exchange rate to get the answer.
$1,166 x 0.2879 = 335.6914
335.6914 rounded to the nearest hundredth (two decimal places) is 335.69
So, it is A, 335.69 dinar.
335.69 dinar Sharon will get in exchange for $1,166 option (a) 335.69 is correct.
What is the ratio?It is defined as the comparison between two quantities that how many times the one number acquires the other number. The ratio can be presented in the fraction form or the sign : between the numbers.
We have a total amount that will need to convert = $1,166
Exchange rate of us dollars to kuwaiti dinar = 1 : 0.2879
It means $1 converted into 0.2879 dinar
The amount $1,166 in kuwaiti dinar = 1166×0.2879
= 335.69 dinar
Thus, 335.69 dinar Sharon will get in exchange for $1,166 option (a) 335.69 is correct.
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Jasmine is trying to replace the flooring in her rectangular bedroom. When she measured the width and length of the floor, she found that the length is 5 ft. longer than the width. If the perimeter of the room is 50 ft., how much flooring will she need to replace the existing flooring in her room?
By finding the area of the rectangle, we will see that she will need 150 ft^2 of flooring.
How to get the area of the rectangle?
For a rectangle of length L and width W, the area is:
A = L*W
And the perimeter is:
P = 2*(L + W).
In this case, we know that the length is 5ft longer than the width, so we can write:
L = W + 5ft
We also know that the perimeter is 50ft, so we can write:
P = 50ft = 2*(W + 5ft + W)
50ft = 4*W + 10ft
40ft/4 = W = 10ft
So the width is 10 ft, and then the length will be:
L = 10ft + 5ft = 15ft
So the area of the rectangle is:
A = 10ft*15ft = 150 ft^2
She will need 150 ft^2 of flooring.
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The expressions (30-2)(30+2) and 30^2-2^2 are equivalent and can help us find the product of two numbers. which two numbers are they?
Answer:
28 and 32
Step-by-step explanation:
The product indicated in your problem statement is ...
(30 -2)(30 +2)
= 28 × 32
The two numbers are 28 and 32.
__
The equivalent (30^2 -2^2) means that product is 900 -4 = 896.
A ladder leans against a 40ft building. The foot of the ladder is 16 feet from the building. About how
long is the ladder? Round to the nearest hundredth
Answer:
60 feet
Step-by-step explanation:
For the holiday blockbuster movie
premier, the Acme theater ran 16
showings for opening day. If each
theater room holds 115 people and each
showing was filled, how many people
viewed the movie on the first day?
A 99 people
B 131 people
c 1,725 people
D 1,840 people
Answer:
1 theater room holds 115 people, it says that each showing was filled so that means that there were 115 for every 1 showing. There were 16 showings, so you multiply 115 x 16 which equals to 1,840 people.
Algebra 1 :
Work must be shown….
write the an equation for linear function f(x) if f(3)=-4 and f(2)=6
What we have been given here are two points.
f(3) = -4 is the same as (3, -4)
f(2) = 6 is the same as (2, 6)
We can then use these two points to find the equation of a line.
Step 1: Find the slope
Slope Formula: (y2 - y1) / (x2 - x1)
Slope = (6 - - 4) / (2 - 3) = (10) / (-1) = -10
Step 2: Find the y-intercept
To find the y-intercept, we'll take our slope and one of our points and plug them into slope-intercept form, then solve for b.
Slope-Intercept Form: y = mx + b
Point = (2, 6)
6 = 2(-10) + b
6 = -20 + b
b = 26
Step 3: Create the equation of the line
Now that we have the slope and y-intercept, all that's left to do is plug both of those values into slope-intercept form.
y = -10x + 26
Answer: y = -10x + 26
Hope this helps!
5 1/2 divided by 3 1/3
Answer:
1 13/20
Step-by-step explanation:
5 1/2 ÷ 3 1/3
11/2 ÷ 10/3
11/2 x 3/10 = 33/20
33/20 = 1 13/20
Hope this helps :)
Answer:
17/62 = 0.27419
Step-by-step explanation:
Hope this helps! Please let me know if you need more help or think my answer is incorrect. Brainliest would be MUCH appreciated. Have a wonderful day!
A family has two children. if b represents a boy and g represents a girl, the set of outcomes for the possible genders of the children is s = {bb, bg, gb, gg}, with the oldest child listed first in each pair. let x represent the number of times g occurs. which of the following is the probability distribution, px(x)? a 2-column table has 3 rows. the first column is labeled x with entries 0, 1, 2. the second column is labeled p x (x) with entries 0.25, 0.5, 0.25. a 2-column table has 3 rows. the first column is labeled x with entries 0, 1, 2. the second column is labeled p x (x) with entries 0.33, 0.33, 0.33. a 2-column table has 3 rows. the first column is labeled x with entries 0, 1, 2. the second column is labeled p x (x) with entries 0.25, 0.75, 0. a 2-column table has 3 rows. the first column is labeled x with entries 0, 1, 2. the second column is labeled p x (x) with entries 0, 0.5, 0.5.
Probability helps us to know the chances of an event occurring. The probability distribution of a girl child being born can be drawn as given below.
What is Probability?The probability helps us to know the chances of an event occurring.
[tex]\rm{Probability=\dfrac{Desired\ Outcomes}{Total\ Number\ of\ outcomes\ possible}[/tex]
As it is given to us that the possible genders of the children,
S = {BB, BG, GB, GG},
And we know that the probability of a girl child can be found using the formula of probability, now, finding the probability of the girl child,
A.) The probability that there is no girl child born,
[tex]\rm{Probability=\dfrac{Desired\ Outcomes}{Total\ Number\ of\ outcomes\ possible}\\\\[/tex]
[tex]\rm P(X=0)=\dfrac{\text{Outcomes in which no girl child is born}}{\text{All the possible values}}[/tex]
[tex]\rm P(X=0)=\dfrac{1}{4} = 0.25[/tex]
B.) The probability that there is one girl child is born,
[tex]\rm{Probability=\dfrac{Desired\ Outcomes}{Total\ Number\ of\ outcomes\ possible}\\\\[/tex]
[tex]\rm P(X=1)=\dfrac{\text{Outcomes in which one girl child is born}}{\text{All the possible values}}[/tex]
[tex]\rm P(X=1)=\dfrac{2}{4} = 0.5[/tex]
C.) The probability that there is two girl child is born,
[tex]\rm{Probability=\dfrac{Desired\ Outcomes}{Total\ Number\ of\ outcomes\ possible}\\\\[/tex]
[tex]\rm P(X=2)=\dfrac{\text{Outcomes in which two girl child is born}}{\text{All the possible values}}[/tex]
[tex]\rm P(X=2)=\dfrac{1}{4} = 0.25[/tex]
The probability distribution of a girl child being born can be drawn as given below.
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Answer:A
Step-by-step explanation:
Help me, please! It's all in the question...!
Answer:
the answer is the first one
Step-by-step explanation:
because
Answer
c hope it helps
If the area of a circular cricket ground is 15,400 m2, then find its circumference. (Take π≈22/7)
Answer:
440m^2
Step-by-step explanation:
15400/(22/7)=4900, which is r^2, so r=70. Now we can find the circumference by doing 22/7*2*70, which is 440.
Find the radius of the circle:
Area of a circle = pi x r^2
15,400 = 22/7 x r ^2
Divide both sides by 22/7
4900 = r^2
Take the square root of bothe sides:
R = 70
The radius of the circle is 70 meters.
now find the circumference:
Circumference = 2 x pi x radius
Circumference = 2 x 22/7 x 70
Circumference = 440 meters
answer: 440 meters
The area of a rectangle is 175 cm. And the width of the rectangle is 5 cm. What's the perimeter of the rectangle?
Answer:
80cm
Step-by-step explanation:
The area of the rectangle is given by Area = L*W (length, L and width, W).
175 cm^2 = 5*L
L = 35 cm
Perimeter is 2L + 2W
2(35cm)+2(5cm)
70cm + 10cm
Perimeter = 80cm
A. Directions/Instructions:
Given
Solution (3 points)
Final Answer (1 point)
Ex. : 5ab( 4a3 + 2ab - 3b4)
=5ab( 4a3 + 2ab - 3b4)
=20a4b+10a2b2-15ab5
=20a4b+10a2b2-15ab5
1. (6k + 5)(5k + 5)
2. (a2+6a-4)(2a-4)
3. (4x2-5x-21)÷(x-3)
Perform the operation on the following algebraic expressions and apply the laws of exponents. (3 points)
B. Directions/Instructions:
Perform the operation on the following algebraic expressions and apply the laws of exponents. (3 points)
Given
Solution (2 points)
Final Answer
Example: 8c52d42
=8c52d42
=64c104d8
=16c10d8
1. (4x5y3)2
2. 18c8(-2c)2
3. 3a2bab24ab2c3c
Answer:
Hope the pictures will help. I have done what I knew
A student has gotten the following grades on his tests. What is the minimum grade he must get on the last test in order to have an average of 787
83, 81, 70, 74
The minimum grade he must get on the last test in order to have an average of 78 is
Answer:
82
Step-by-step explanation:
The sum of his previous grades were 308. In order to get an average grade of 78, he needs to have a score of 78*5 or 390. His necessary grade minus his current grade is 390 - 308, which is 82. The minimum score the student needs to get on his test in order to have an average of 78 is 82
Answer:
82.
Step-by-step explanation:
The sum of the 5 tests must be 5*78 = 390 for the average to be 78.
So in the last test is grade must be 390 - (83+81+70+74)
= 390 - 308 = 82.
Which measurement is more precise? 45 fluid ounces or 79 cups
Answer:
45 fluid ounces
Step-by-step explanation:
Weight will be more accurate and consistent
To think of it simply, you may not always fill a measuring cup completely to the top and never spill out of it, weight is a given, cup measurements turn into a very close measurement that isn't 100% exact
L1S2
Area - Compound Shapes
Find the area of the shaded region in each figure. Round your answer to 2 decimal
places if required. (Use = 3.14)
PLEASE HELP I WILL MARK BRAINLIEST!
Answer:
just trust yourself
Step-by-step explanation:
What is the surface area of each figure 11 m 7 m 6 m?
Answer:
hi, I'm glad to help! 185
Step-by-step explanation:
11*7=77
11*6=66
6*7=42
77+66+42=185
What is the radius of a circle given by the equation x2 y2 – 2x 8y – 47= 0?
Answer:
the answer is 8 units
Step-by-step explanation:
The radius of a circle given by the equation [tex]\rm x^2+y^2-2x+8y-47=0[/tex] is 8 units.
It is given that the circle equation is given by [tex]\rm x^2+y^2-2x+8y-47=0[/tex]
It is required to find the radius of the circle.
What is a circle?It is defined as the combination of points that and every point has an equal distance from a fixed point ( called the center of a circle).
We circle the equation:
[tex]\rm x^2+y^2-2x+8y-47=0[/tex]
Converting this equation into the standard form of the circle:
[tex]\rm (x-a)^2+(y-b)^2=r^2[/tex]
[tex]\rm x^2+y^2-2x+8y-47=0[/tex]
[tex]\rm x^2+y^2-2x+8y-47+1-1+16-16=0[/tex] (by adding and subtracting by
1 and 16)
[tex]\rm x^2-2x+1+y^2+8y+16-1-16-47=0\\\\\rm (x-1)^2+(y-(-4))^2-64=0\\\\\rm (x-1)^2+(y-(-4))^2=64\\\\\rm (x-2)^2+(y-(-4))^2=8^2 \\\\[/tex]
By comparing with the standard circle equation, we get:
r = 8
Thus, the radius of a circle given by the equation [tex]\rm x^2+y^2-2x+8y-47=0[/tex] is 8 units
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CAN SOMEONE PLEASE HELP
[tex]\qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]
Here's the solution ~
[tex]\qquad \sf \dashrightarrow \: \dfrac{2 {}^{n} - 1}{ {4}^{n} - 1} [/tex]
[tex]\qquad \sf \dashrightarrow \: \dfrac{2 {}^{n} - 1}{ {( {2}^{2}) }^{n} - 1} [/tex]
[tex]\qquad \sf \dashrightarrow \: \dfrac{2 {}^{n} - 1}{ {( {2}^{n}) }^{2} - 1} [/tex]
Now we will use this identity in denominator
[ a² - b² = (a + b)(a - b) ]
[tex]\qquad \sf \dashrightarrow \: \dfrac{ \cancel{(2 {}^{n} - 1)}}{ {( {2}^{n} }^{} + 1) \cancel{( {2}^{n} - 1)}} [/tex]
[tex]\qquad \sf \dashrightarrow \: \dfrac{ 1}{ {( {2}^{n} }^{} + 1) } [/tex]
Answer:
[tex]\sf \dfrac{1}{2^n+1}[/tex]
Step-by-step explanation:
Given expression:
[tex]\sf \dfrac{2^n-1}{4^n-1}[/tex]
Rewrite [tex]\sf 4^n[/tex]: [tex]\sf 4^n=(2^2)^n=2^{2n}=(2^n)^2[/tex]
Rewrite 1: 1 = 1²
[tex]\sf \implies \dfrac{2^n-1}{(2^n)^2-1^2}[/tex]
Apply difference of two square formula to the denominator
[tex]\sf a^2-b^2=(a+b)(a-b)[/tex]
[tex]\sf \implies \dfrac{2^n-1}{(2^n+1)(2^n-1)}[/tex]
Cancel out the common factor [tex]\sf 2^n-1[/tex] :
[tex]\sf \implies \dfrac{1}{2^n+1}[/tex]