Question

The product of (7p-8q)(7p+8q) will be *​

Answer 1

We use identity (a+b)(a-b)=a2-b2

Given (7p+8q)(7p-8q)

here a=7p and b =8q

So by the above identity

we get,

(7p+8q)(7p-8q)

=(7p)2-(8q)2

=7×7×p×p-8×8×q×q

=49p2-64q2