## anonymous one year ago If f(x) = x+ tan x and g(x) is the inverse of f(x) then g'(x) is equal to..

1. anonymous

@ganeshie8

2. ganeshie8

aren't you trying to find the derivative of inverse at a particular point ?

3. anonymous

answer is 1/(2+{g(x) - x}^2) and i have no clue

4. Empty

That doesn't seem right to me

5. anonymous

at a particular point it would be easy na

6. ganeshie8

maybe start with this : $f(g(x)) = x$

7. Empty

Since it's the inverse I plugged it in to get: $x=g(x)+\tan g(x)$ Then differentiate: $1=g'(x)+g'(x)\sec^2g(x)$ $g'(x)=\frac{1}{1+\sec^2 g(x)}$

8. Empty

Well that's why I said it doesn't seem right idk depends on what kind of answer you're looking for I guess.

9. anonymous

thanks i get it... converting sec^2 g(x) to tan ^2 g(x) then substituting tan^2 from the eqn f(g(x)) = x

10. ganeshie8

Nice :)