Mathematics · 2021
JEE Main · 31 August 2021, Shift 1 · Q65
Three numbers are in an increasing geometric progression with common ratio r. If the middle number is doubled, then the new numbers are in an…
Three numbers are in an increasing geometric progression with common ratio r . If the middle number is doubled, then the new numbers are in an arithmetic progression with common difference d. If the fourth term of GP is $\displaystyle 3 \mathrm{r}^2$, then $\displaystyle \mathrm{r}^2-\mathrm{d}$ is equal to :
Official answer
(2)
$\displaystyle 7+\sqrt{3}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.