Assertion (A): The 9th term of a Geometric Progression (G.P.) 6, −12, 24, −48, ... is a positive term. Reason (R): The value of (−2)8 is always positive. 1. (A) is true and (R) is false. 2. (A) is false and (R) is true. 3. Both (A) and (R) are true and (R) is the correct explanation of (A). 4. Both (A) and (R) are true but (R) is not the correct explanation of (A).

Question

KnowledgeBoat · Accepted Answer

Given, 6, −12, 24, −48... is a G.P. a = 6 r = = -2 By formula, an = arn - 1 For 9th term, ⇒ a9 = (6).(-2)9 - 1 = 6.(-2)8 = 6.(256) = 1536 0. Assertion (A) is true. (-2)8 Any negative number raised to an even power is always positive. Reason (R) is true. Thus, both (A) and (R) are true and (R) is the correct explanation of (A). Hence, option 3 is the correct option.

Mathematics

G.P.

Answer

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