# Need inverse function help

#### ATCG

Could somebody please explain to me how you would calulate the inverse functions of x^3+4x+1. And if possible how you would calulate that on the TI-83 graphing calculator. Thanks

#### Hurkyl

Staff Emeritus
Gold Member
Could somebody please explain to me how you would calulate the inverse functions of x^3+4x+1.
You don't.

The exact formula for the inverse of this function requries the cubic formula, which is fairly complicated (although in this case the result is readable), and is almost certainly not what you are expected to do in class; there's probably a way to find the answer to your problem without having to explicitly compute this inverse.

#### ATCG

It is expected. If you know how to solve this equation please tell me.

#### Hurkyl

Staff Emeritus
Gold Member
I see you've found the cubic formula. Do you still need help with it?

I'm curious what the actual text of the problem is.

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