Math Is Fun Forum

reconsideryouranswer

Member

Registered: 2011-05-11

Posts: 171

Issues with the inverse functions page

From:

http://www.mathsisfun.com/sets/function-inverse.html

"Not Always Solvable!

It is sometimes not possible to find an Inverse of a Function.

Example: f(x) = x/2 + sin(x)

We cannot work out the inverse of this, because we cannot solve for "x":

y = x/2 + sin(x)

y ... ? = x"

This function isn't even one-to-one, so by default, a person cannot
find an inverse for it, because the inverse does not exist for it.

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Also, you could mention that certain functions are inverses of themselves.

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MathsIsFun

Administrator

Registered: 2005-01-21

Posts: 7,713

Re: Issues with the inverse functions page

But we can easily choose an interval where it is one-to-one, say [0,2]. Is it then solvable?

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"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman