`finverse`

Inverse of a function of one variable.

Category: Mathematics > Equation Solving

Syntax

g = finverse(f)

Returns the inverse of f in its default variable.

g = finverse(f, x)

Inverts with respect to the variable x.

Description

finverse solves y = f(x) for x and returns the result written in the variable x again. The inverse is valid on the branch where f is one-to-one; for a non-injective f such as x^2 only one branch is given.

Input arguments

f: Symbolic expression that is one-to-one in x.
x: Variable to invert for.

Output arguments

g: Symbolic expression such that f(g(x)) is x.

Example

Inverting linear and exponential functions

syms x
finverse(2*x + 3, x)
finverse(exp(x))

Output

ans = x/2 - 3/2
ans = log(x)

finverse