Mathematics · 2024
JEE Main · 29 January 2024, Shift 2 · Q6
If each term of a geometric progression a_1, a_2, a_3, …. with a_1=1/8 and a_2 ≠ a_1, is the arithmetic mean of the next two terms and…
If each term of a geometric progression $\displaystyle a_1, a_2, a_3, \ldots$. with $\displaystyle a_1=\frac{1}{8}$ and $\displaystyle a_2 \neq a_1$, is the arithmetic mean of the next two terms and $\displaystyle S_n=a_1+a_2+\ldots . .+a_n$, then $\displaystyle S_{20}-S_{18}$ is equal to
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle -2^{15}$
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.