CUET Preparation Today
CUET
General Test
Quantitative Reasoning
Trigonometry
If \frac{cosA}{cosecA+1}+\frac{cosA}{cosecA-1}= 2, 0° ≤ A ≤ 90°, then A is equal to : |
60° 45° 90° 30° |
45° |
Given :- \frac{cosA }{cosecA + 1 } + \frac{cosA }{cosecA - 1 } = 2 \frac{cosA ( cosecA-1) + cosA(cosecA +1 ) }{cosec²A - 1 }= 2 We know , { cosec²A - 1 = cot²A } \frac{2cosA.cosecA }{cot²A }= 2 \frac{cosA.cosecA }{cos²A / sin²A } = 1 \frac{cosecA }{cosA / sin²A } = 1 tanA = 1 Ans we know that , tan45º = 1 So, A = 45º
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