Mathematics · 2021
JEE Main · 31 August 2021, Shift 2 · Q83
If the coefficient of a^7 b^8 in the expansion of ( a +2 b +4 ab )^10 is K · 2^16, then K is equal to \ \ \ \.
If the coefficient of $\displaystyle \mathrm{a}^7 \mathrm{~b}^8$ in the expansion of $\displaystyle (\mathrm{a}+2 \mathrm{~b}+4 \mathrm{ab})^{10}$ is $\displaystyle \mathrm{K} \cdot 2^{16}$, then K is equal to
\_\_\_\_.
Official answer
315
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.