Assertion (A): The 9th term of the G.P. 6, −12, 24, −48, … is positive.
Reason (R): (−2)⁸ is positive.
(a) A is true and R is false.
(b) A is false and R is true.
(c) Both A and R are true and R is the correct explanation of A.
(d) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are true and R is the correct explanation of A.
Explanation:
Here, first term a = 6 and common ratio r = −2.
The nth term of a G.P. is Tₙ = arⁿ⁻¹.
T₉ = 6(−2)⁸
Since (−2)⁸ is positive, T₉ is positive.
Therefore, both A and R are true, and R correctly explains A.
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