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

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

#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

Let's go through the process step by step to find any mistakes.

#1: f(x+1) = 8(x+1)(x+1) + x - 3

To expand this expression using FOIL, you need to multiply each term in the first parentheses by each term in the second parentheses. Let's do it correctly:

8(x+1)(x+1) = 8(x^2 + x + x + 1)

Now you need to combine like terms:

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

Distribute the 8:

= 8x^2 + 16x + 8 + x - 3

Combine like terms:

= 8x^2 + 17x + 5

So the correct expansion is: f(x+1) = 8x^2 + 17x + 5

It seems like you made an error in the combination of terms.

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

To solve this, let's simplify the expression by performing the necessary calculations:

8(-x)^2 = 8x^2

(-x) - 3 = -x - 3

Combining the terms, we have:

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

Since (-x) is the same as -x, we can write it as:

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

So the correct expression is: f(-x) = 8x^2 - x - 3

It seems like you made an error in the sign of the middle term.

Remember to double-check your work and carefully combine like terms to avoid mistakes.