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MathsMediumMCQ2016 · 03 Apr

Q62.A value of θ for which 2+3i sin θ is purely imaginary, is 1−2i sin θ (1) sin−1( √34 ) (2) sin−1( √31 ) (3) π (4) π 3 6

What This Question Tests

This question tests the ability to perform division of complex numbers and identify the condition for a complex number to be purely imaginary (real part equals zero). It then requires solving a trigonometric equation.

Concepts Tested

Complex numbers divisionPurely imaginary numbersEquating real part to zeroTrigonometric equations

Formulas Used

(a+bi)/(c+di) = [(ac+bd) + i(bc-ad)] / (c^2+d^2)

sin^2(θ) + cos^2(θ) = 1

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