Mathematics · 2026
JEE Main · 6 April 2026, Shift 2 · Q22
If (1-x^3)^10=Σ_r =0^10 a_r x^r (1-x)^30-2 r, then (9 a_9)/(a_10) is equal to ____.
If $\displaystyle \left(1-x^3\right)^{10}=\sum_{\mathrm{r}=0}^{10} \mathrm{a}_{\mathrm{r}} x^{\mathrm{r}}(1-x)^{30-2 \mathrm{r}}$, then $\displaystyle \frac{9 \mathrm{a}_9}{\mathrm{a}_{10}}$ is equal to $\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
30
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.