Mathematics · 2021
JEE Main · 3 August 2021, Shift 1 · Q85
Let n ≥ 1 be an odd integer and S_n=n^3-(n-1)^3+(n-2)^3-…+(-1)^n-1 1^3. If S_199-4 S_99=10^6 λ, then the value of λ is \ \ \ \.
Let $\displaystyle n \geq 1$ be an odd integer and $\displaystyle \mathrm{S}_n=n^3-(n-1)^3+(n-2)^3-\ldots+(-1)^{n-1} 1^3$. If $\displaystyle \mathrm{S}_{199}-4 \mathrm{~S}_{99}=10^6 \lambda$, then the value of $\displaystyle \lambda$ is \_\_\_\_.
Official answer
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.