Question

Show that:
1. (4pq + 3q)2 – (4pq – 3q)2 = 48pq2
2. (a – b)(a + b) + (b – c) (b + c) + (c – a) (c + a) = 0

Answer 1

Answer:

$1. )\: {(4pq + 3q)}^{2} - {(4pq - 3q)}^{2} = {48pq}^{2} \\ = 16pq + 9q - 16pq - 9q = 2304pq \\ = (16 - 16)pq + (9 - 9)q = 2304pq \\ = 0 + 0 = 2304pq \\ 2304pq$