How do you find the inverse of #f(x)=(x+2)^2-4#?

1 Answer
George C.
Jan 19, 2016

This function is not one-one, so has no well defined inverse unless you restrict the domain.

Explanation:

Note that #f(-3) = f(-1) = -3#, so #f^(-1)(-3)# is not well defined.

If we restrict the domain of #f(x)# it is possible to construct an inverse.

For example, if the domain of #f(x)# is #[-2, oo)# then

#f^(-1)(y) = sqrt(y+4)-2#

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