Mathematics · 2025
JEE Main · 7 April 2025, Shift 2 · Q21
The sum of the series 2 × 1 ×^20 C_4-3 × 2 ×^20 C_5+4 × 3 ×^20 C_6-5 × 4 ×^20 C_7+⋯ ⋯+18 × 17 ×^20 C_20, is equal to ____.
The sum of the series
$\displaystyle 2 \times 1 \times{ }^{20} C_4-3 \times 2 \times{ }^{20} C_5+4 \times 3 \times{ }^{20} C_6-5 \times 4 \times{ }^{20} C_7+\cdots \cdots+18 \times 17 \times{ }^{20} C_{20}$, is equal to
$\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
34
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.