Question 4(v)
Simplify:
(2.5p−1.5q)2−(1.5p−2.5q)2
(2.5p−1.5q)2−(1.5p−2.5q)2 =(2.5p)2−2×2.5p×1.5q+(1.5q)2−[(1.5p)2−2×1.5p×2.5q+(2.5q)2]
[Using identity (a−b)2=a2−2ab+b2]
=6.25p2−7.50pq+2.25q2−[2.25p2−7.50pq+6.25q2] =6.25p2−7.50pq+2.25q2−2.25p2+7.50pq−6.25q2
=4p2−4q2