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If P, Q Be Two A.M.'S and G Be One G.M. Between Two Numbers, Then G2 = - Mathematics

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प्रश्न

If pq be two A.M.'s and G be one G.M. between two numbers, then G2

पर्याय

  • (a) (2p − q) (p −  2q)

  • (b) (2p − q) (2q − p)

  • (c) (2p − q) (p + 2q)

  • (d) none of these

MCQ
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उत्तर

(a) (2p − q) (p − 2q

\[\text{ Let the two numbers be a and b } . \]
\[\text{ a, p, q and b are in A . P } . \]
\[ \therefore p - a = q - p = b - q \]
\[ \Rightarrow p - a = q - p \text{ and } q - p = b - q\]
\[ \Rightarrow a = 2p - q \text{ and } b = 2q - p (i)\]
\[\text{ Also, a, G and b are in G . P }. \]
\[ \therefore G^2 = ab\]
\[ \Rightarrow G^2 = \left( 2p - q \right)\left( 2q - p \right)\] 

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पाठ 20: Geometric Progression - Exercise 20.8 [पृष्ठ ५८]

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आरडी शर्मा Mathematics [English] Class 11
पाठ 20 Geometric Progression
Exercise 20.8 | Q 16 | पृष्ठ ५८

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