We know sin36∘=410−25
Let x=410−25
On squaring both sides, we get
(4x)2=10−25⇒16x2=10−25
Again squaring, we get
(5)2=(5−8x2)2 ⇒5=25+64x4−80x2
⇒16x4−20x2+5=0
JEE Main 2022 — Mathematics Trigonometry
α=sin36∘ is a root of which of the following equation
Held on 27 Jun 2022 · Verified 6 Jul 2026.
16x4−20x2+5=0
16x4+20x2+5=0
10x4−10x2−5=0
16x4−10x2+5=0
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