I have been trying this for 2 days and I can"t seem to get the right answer \

when f(x) =(x+1)

and f(x) = (-x)

when its (x-1) i get the following

2(x-1)^2 +7(x-1)-8

2x^2-4x+2+7x+7x-8

2x^2+3x-1 Is my solution right?

And -X i am just not sure I got 2x^2-8x-8 this as my answer