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2 years ago

If f(x) and f–1(x) are inverse functions of each other and f(x)=2x+5, what is f–1(8)?

Mathematics

2 answers:

yarga [219]2 years ago

6 0

f(x)=2x+5

first find inverse

write it without f(x)

y = 2x + 5

x = 2y + 5 swap the variables, now solve for y

- 5 -5

x - 5 = 2y

/2 /2 divide both sides by 2

(x-5)/2 = y

so f-1(x) = (x-5)/2

f-1(8) = (8-5)/2

= (3)/2

f-1(8) = 3/2

Roman55 [17]2 years ago

4 0

Answer:

3/2

Step-by-step explanation:

f(x)=2x+5

first find inverse (write it without f(x))

y = 2x + 5

x = 2y + 5 (swap the variables, now solve for y)

- 5 -5

x - 5 = 2y

/2 /2 (divide both sides by 2)

(x-5)/2 = y

so f-1(x) = (x-5)/2

f-1(8) = (8-5)/2

= (3)/2

f-1(8) = 3/2

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2 years ago

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2 years ago

The 99 percent confidence interval for the average weight of a product is from 71.36 lbs. to 78.64 lbs. Can we conclude that μ i

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Step-by-step explanation:

Hello!

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