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If A, B, C Are in G.P., Prove That: a (B2 + C2) = C (A2 + B2)

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Question

If a, b, c are in G.P., prove that:

a (b2 + c2) = c (a2 + b2)

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Solution

a, b and c are in G.P.

\[\therefore b^2 = ac\]   .......(1)

\[\text {LHS } = a\left( b^2 + c^2 \right)\]

\[ = a b^2 + a c^2 \]

\[ = a\left( ac \right) + c\left( b^2 \right) \left[ \text { Using } (1) \right]\]

\[ = c\left( a^2 + b^2 \right) = \text { RHS }\]

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Chapter 20: Geometric Progression - Exercise 20.5 [Page 46]

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RD Sharma Mathematics [English] Class 11
Chapter 20 Geometric Progression
Exercise 20.5 | Q 8.1 | Page 46

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