f(x)=(221−x+21+x+3x+3−x)
⇒f(x)=(22(3−x+3x)+(3x+3−x))
⇒f(x)=((3−x+3x)+(23x+3−x))
Using AM≥GM
f(x)≥3
JEE Main 2020 — Mathematics Algebra
Let f:R→R be such that for all x∈R(21+x+21−x),f(x) and (3x+3−x) are in A.P., then the minimum value of f(x) is
Held on 8 Jan 2020 · Verified 6 Jul 2026.
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