Question

If f(n) = 2n^2 + 2 and g(n) = n + 1, what is (f -g)(n) when n = -1?

Answer 1

the easiest way is to first subtract them first and then replace n with -1:
2n^2+2-n-1 => 2n^2-n+1
now we replace n with -1
2(-1)^2-(-1)+1 => 2+2=4
"4" is teh final answer