Question

How do you find 2p(a) + p(a - 1) if `p(x) = x^2 + x`?

Answer 1

`2p(a)+p(a-1)=3a^2+a`.

Explanation:

Given poly. `p(x)=x^2+x`

To find `p(a)`, we have to just put `a`, in place of `x`,

Hence, `p(a)=a^2+a`, and, `p(a-1)=(a-1)^2+(a-1)=(a-1)(a-1+1)=a(a-1)`.

Therefore, `2p(a)+p(a-1)=2(a^2+a)+a(a-1)=2a^2+2a+a^2-a=3a^2+a`.