If Cot x/Cot y = A and Cosec x/Cosec y = B, then the value of Cosec y in terms of A and B.
If Cot x/Cot y = A and Cosec x/Cosec y = B, then the value of Cosec y in terms of A and B. Correct Answer <p>√((1 – A<sup>2</sup>)/(B<sup>2</sup> – A<sup>2</sup>))</p>
Given
Cot x/Cot y = A and Cosec x/Cosec y = B
Concept
Cosec2 A – Cot2A = 1
Calculation
Cot x = A Cot y
Squaring on both sides
Cot2x = A2Cot2y
⇒ Cosec 2x – 1 = A 2 (Cosec 2 y – 1) ---- (1)
Cosec x = B Cosec y
Squaring on both sides
⇒ Cosec 2x = B 2Cosec 2 y ---- (2)
From (1) and (2)
B2Cosec2y – 1 = A2Cosec2y – A2
⇒ B2Cosec2y – A2Cosec2y = - A2 + 1
⇒ Cosec2y(B2– A2) = - A2+ 1
⇒ Cosec y = √((1 – A2)/(B2 – A2))
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Feb 20, 2025