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Question
Find the value of a, if pqa = (3p + q)2 – (3p – q)2
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Solution
We have,
pqa = (3p + q)2 – (3p – q)2
⇒ pqa = [(3p + q) + (3p – q)][(3p + q) – (3p – q)] ...[Using the identity, a2 – b2 = (a + b)(a – b)]
⇒ pqa = [(3p + q + 3p – q)][3p + q – 3p + q]
⇒ pqa = 6p × 2q
⇒ `a = (6p xx 2q)/(pq) = ((6 xx 2)pq)/(pq)`
⇒ a = 12
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