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MathsMediumMCQ2023 · 24 Jan Shift 2

Q61.The number of real solutions of the equation 3(x2 + x21 ) −2(x + x1 ) + 5 = 0 , is (1) 4 (2) 0 (3) 3 (4) 2 2π 2π 3 1+sin 9 +i cos 9

What This Question Tests

This question tests the ability to solve a reciprocal type equation by appropriate substitution and then determine the number of real solutions by analyzing the discriminant of the resulting quadratic equations.

Concepts Tested

Reciprocal equationsSubstitution methodDiscriminant for real roots

Formulas Used

x + 1/x = t

x^2 + 1/x^2 = t^2 - 2

D = b^2 - 4ac

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