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What is the inverse of function f? F(X) = square root of x +7

User Toni Vanhala
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2 Answers

8 votes
8 votes

Answer:

f⁻¹=x²+7

Solution:

  • In order to find the inverse of a function, we should first replace f(x) with y, then switch x and y places, like so:
  • y=√x+7
  • x=√y+7
  • Now, solve the equation for y.
  • Square both sides in order to get rid of the square root:
  • x²+7=y
  • y=x²+7
  • And finally, replace y with f⁻¹:
  • f⁻¹=x²+7
  • Also, inverse functions do the opposite thing in the opposite order.
  • So if we have f(x)=x+7, the inverse function is: f⁻¹=x-7

Hope it helps.

Do comment if you have any query.

User Sebastian Olsen
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2.8k points
24 votes
24 votes

Answer:
f^(-1) (x)=x^(2) -7

Explanation:

To find the inverse of a function replace f(x) with x and the original x with y


f(x)=√(x+7) \\x=√(y+7)

Now we can solve for y

Square both sides so we can cancel out the root


x=√(y+7)\\x^(2) =√(y+7)^(2) \\x^(2) =y+7

Now subtract 7 from both sides


x^(2) =y+7\\x^(2) -7=y+7-7\\x^(2) -7=y

Now replace y with the inverse of f(x),
f^(-1) (x)

User Dylan Maxey
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2.7k points