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

1 Answer
Jan 24, 2016

#f^-1(x)=sqrt{(2-x)/2}#

Explanation:

The function if defined as #f(x)=y# then the inverse would be #f^-1(y)=x#

Now, given #f(x)=2-2x^2# so #y=2-2x^2#
Subtracting by #2# on both sides and then multiplying by #-1# we get
#2-y=2x^2#,
let's divide by #2# now.
So, #(2-y)/2=x^2# Now, taking the square root, we get
#\sqrt{(2-y)/2}=x# and if you see above, #f^-1(y)=x#.
So the answer is as given above. (just replace #y# with #x#)