Mathematics · 2026
JEE Main · 22 January 2026, Shift 2 · Q21
Suppose a, b, c are in A.P. and a^2, 2 b^2, c^2 are in G.P. If a < b < c and a + b + c =1, then 9( a^2+ b^2+ c^2) is equal to ____.
Suppose $\displaystyle \mathrm{a}, \mathrm{b}, \mathrm{c}$ are in A.P. and $\displaystyle \mathrm{a}^2, 2 \mathrm{~b}^2, \mathrm{c}^2$ are in G.P. If $\displaystyle \mathrm{a}<\mathrm{b}<\mathrm{c}$ and $\displaystyle \mathrm{a}+\mathrm{b}+\mathrm{c}=1$, then $\displaystyle 9\left(\mathrm{a}^2+\mathrm{b}^2+\mathrm{c}^2\right)$ is equal to $\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
9
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.