Thread: inverse functions

i need to find the inverse of f(x) = x^2-4x+3 how do you do it when you have x^2 and x?

Originally Posted by katt

i need to find the inverse of f(x) = x^2-4x+3 how do you do it when you have x^2 and x?

complete the square.

Y=x^2-4x+3 => x^2-4x+3-y=0

delta'=4-3+y=1+y

=> x1=2+squareroot(1+y)
and x2=2-squareroot(1-y)

this is the inverse you choose x1 or x2 depending on the constrains given .

swap x and y ...









restrict the domain of the original function to , and the inverse function is