Mark M. answered • 11/28/16
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The graph of the function h(x) = -3 is a horizontal line. So, the graph fails the horizontal line test (in other words, the function is not one to one). Consequently, h(x) does not have an inverse function.
Mark M.
tutor
If the function is h(x) = -3, then my answer is correct. Did you leave out part of the question? Please repost the ENTIRE question.
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11/28/16
CONTESSA M.
There is a list of functions for us to chose from. The available choice was h(x)=-3. The problem is as follows:
Check that (f°f-1)(x)=x and (f-1°f)(x)=x
"Select and determine the inverse f1 of one of the following functions.
Show and Explain your work."
h(x)=-3
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11/28/16
Mark M.
tutor
"Select and determine the inverse f-1 of one of the following functions". The function selected (h(x) = -3) does not have an inverse function, as I explained earlier. If you send me a list of the functions to choose from, I would be glad to select one that does have an inverse.
Mark M (Bayport, NY)
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11/28/16
CONTESSA M.
r(x)=2x-8
s(x)=-1/x (negative one over x)
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11/28/16
Mark M.
tutor
r(x) = 2x-8 has an inverse function since the graph passes the horizontal line test. To find the inverse function, proceed as follows:
Step 1: let y = 2x-8
Step 2: switch x and y to get x = 2y-8
Step 3: solve for y: y = (x+8)/2
So, r-1(x) = (x+8)/2
Check: r(r-1(x)) = r((x+8)/2) = 2[(x+8)/2)] -8 = x+8-8 = x
r-1(r(x)) = r-1(2x-8) = [(2x-8)+8]/2 = 2x/2 = x
Mark M (Bayport, NY)
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11/28/16
CONTESSA M.
11/28/16