Inverse of a Function

[PsySc0rpi0n Profile]

Hello again.

I know I can plot te inverse of a function. But is it possible to analytically evaluate the expression of the inverse function of a given expression?

[lephe Profile]

You could just rotate the calculator 90°. Otherwise you're stuck with the serious problem that only few functions are invertible; an analytical inversion process seems out of the question. Even polynomials are mostly not injective, so you're definitely not going to get an expression by calling a built-in calculator functionality.

[PsySc0rpi0n Profile]

Well, maybe if I describe the problem, it gets easier to understand.

I'm testing an electronic circuit and I'm registering some values I'm reading with the scope from that circuit. With those values, I plot a curve in a Spreadsheet. Then I ask the Spreadsheet program to give me the Trend Line expression using the Quadratic Law. After that I wanted to obtain the inverse function of the expression SpreadSheet gave me. I'm doing it by hand but if the calculator could give it to me, it was great!