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If 12cot2θ - 31cosecθ + 32 = 0, 0° < θ < 90° then the value of tanθ will be:

A. $$\frac{4}{3},\,\frac{{3\sqrt 7 }}{7}$$

B. $$\frac{4}{5},\,\frac{{5\sqrt 7 }}{7}$$

C. $$\frac{5}{4},\,\frac{4}{3}$$

D. $$\frac{4}{5},\,\frac{4}{3}$$

Answer: Option A

Solution(By Examveda Team)

12cot2θ - 31cosecθ + 32 = 0
12cosec2θ - 12 - 31cosecθ + 32 = 0
12cosec2θ - 31cosecθ + 20 = 0
12cosec2θ - 16cosecθ - 15cosecθ + 20 = 0
4cosecθ(3cosecθ - 4) - 5(3cosecθ - 4) = 0
(4cosecθ - 5)(3cosecθ - 4) = 0
cosecθ = $$\frac{5}{4}$$, cosecθ = $$\frac{4}{3}$$
Trigonometry mcq question image
$$ = \frac{{\sqrt 7 \times 3}}{7}$$

Alternate:
Go through option A
Trigonometry mcq question image
12cot2θ - 31cosecθ + 32 = 0
$$\eqalign{ & 12 \times \frac{9}{{16}} - \frac{{31 \times 5}}{4} + 32 = 0 \cr & 0 = 0 \cr} $$

This Question Belongs to Arithmetic Ability >> Trigonometry

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