How to get the inverse function

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​1.- For getting the inverse of a function, you ALWAYS need it to be in this form:

y=a (x - h)2 +k

Example:

y=(x-4) 2 -9

In case it is expressed in this form:

y=ax2 +bx+c

y= x2 -8x+7=0

You need to convert it.

(If you don’t know how to convert it, please go to section 3)

2.- First, you need to substitute x per y and y per x.

y=(x-4) 2 -9

x= (y-4)2-9

Then, you just need to isolate for y.

(y-4)2-9=x

(y-4)2=x+9

y-4= -+ √ x+9

y= 4 -+ √ x+9

You got the inverse function!