Question

expand the following
a) (5x-3)²
b) (pq²-5)²
c) (x-y)²-(x+y)²
​

Answer 1

a) ${\red{\sf{(5x-3)²=25x²-30x+9}}}$

b) ${\red{\sf{(pq²-5)²=p²q⁴-10pq²+25}}}$

c) ${\red{\sf{(x-y)²-(x+y)²=-4xy}}}$