If P + Q = 8 and P - Q = 4, Find: P2 + Q2

If p + q = 8 and p - q = 4, find:
p²+ q²

Sum

Putting pq = 12 in (i) we get :
p² + q²
= 64 - 2(12)
= 64 - 24
= 40.

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Chapter 4: Expansions - Exercise 4.1

Chapter 4 Expansions
Exercise 4.1 | Q 12.2

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