Question bank/JEE Main/Mathematics
JEE MainMathematicsModerateQuadratic Equations
1 3x^2 - 3(sin) θξ - 2cos^2θ = 0
sinθ
Show answer and solution
Since coefficient of x^2 > 0 & 1 lies between root.
∴ f(1) < 0
as 3 - 3sinθ - 2cos^2θ < 0
⇒ 3 - 3σινθ - 2 (1-sin^2θ) < 0
2sin^2θ - 3sinθ + 1 < 0
(2sinθ -1) (sinθ -1) < 0
∴ f(1) < 0
as 3 - 3sinθ - 2cos^2θ < 0
⇒ 3 - 3σινθ - 2 (1-sin^2θ) < 0
2sin^2θ - 3sinθ + 1 < 0
(2sinθ -1) (sinθ -1) < 0
Source: Grass-G / M-04 Paper 2 Mathematics 18-8-2020_Final.docx
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