Question

What is the standard form of a polynomial `(j + 7)(j – 7)`?

Answer 1

`(j+7)(j-7)=(j^2+7^2) =49+j^2`

If as complex number form then
`(j+7)(j-7)=48`

Explanation:

Compare to `(a^2-b^2)=(a-b)(a+b)`

So `(j+7)(j-7)=(j^2+7^2) =49+j^2`

If you are using `j` as the same as complex number `i`

Then `j^2 =-1` giving:

`(j+7)(j-7)=48`