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Sequences and Series question

2023 · 6 Apr · Shift 2 · Q43

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JEE Main
Mathematics
Sequences and Series
2023 · 6 Apr · Shift 2 · Q43

Sequences and Series question

2023 · 6 Apr · Shift 2 · Q43

JEE MainMathematicsSequences and SeriesNumerical+4 / −1

If

(20)^{19}+2(21)(20)^{18}+3(21)^{2}(20)^{17}+\ldots+20(21)^{19}=k(20)^{19}

, then

k

is equal to

\underline{\hspace{2cm}}

.

Numerical answer

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