How do you find the inverse of $y = 2x^2 - 3x +1$ and is it a function?

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Answer 1 · 2016-06-05T20:48:57

To find the inverse you need to write $x=$ something, then it is exactly the same way as to solve the second order equation:

$y=2x^2-3x+1$

$2x^2-3x+1-y=0$

$x=(3\pm sqrt(9-4*2*(1-y)))/4$

$x=(3\pm sqrt(1-8y))/4$ .

This is the inverse. It is not a function because for one $y$ you have two $x$ , one with the plus solution and one with the minus.

How do you find the inverse of y = 2x^2 - 3x +1y = 2x^2 - 3x +1 and is it a function?