f(x+1)=8x^2+x-3

Question

f(-x)=8x^2+x-3

work:
#1 8(x+1)(x+1)+x-3 then FOIL
8(x^2+x+x+2)+x-3
8x^2+16x+16+x-3
*8x^2+17x+13
#2 8(-x)^2-x-3
8x-x-3
*7x-3

I know on the first one you FOIL but im still getting it wrong?? The second one i thought was simple but im getting it wrong

Answer 1

#1 8(x+1)(x+1)+x-3 then FOIL
8(x^2+x+x+2)+x-3 ****Nope, lots of errors, so here is what it should be..
8(x^2+x+x+1)+ (x+1)-3

2)8(-x)^2 + (-x) -3
8x^2-x-3