Mathematics · 2018
JEE Main · 16 April 2018, Shift 1 · Q69
The sum of the first 20 terms of the series 1+3/2+7/4+15/8+31/16+…, is:
The sum of the first $\displaystyle 20$ terms of the series $\displaystyle 1+\frac{3}{2}+\frac{7}{4}+\frac{15}{8}+\frac{31}{16}+\ldots$, is :
Official answer
(1)
$\displaystyle 38+\frac{1}{2^{19}}$
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JEE Main 2018 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.