( *)If tan theta 1 = k cot theta 2 then cos (theta1 – theta2) / cos (theta1 + theta 2) =

Hello student, Please find the answer to your question below

tan Ø ₁ = k cotØ ₂
=> tan Ø 1 * tanØ ₂ = k

Now cos (theta1 – theta2) / cos (theta1 + theta 2)
=[cos Ø1 cos Ø2 – sin Ø1 sin Ø2] / [cos Ø1 cos Ø2 + sin Ø1 sin Ø2]
Divide numerator and denomenator by cos Ø1 cos Ø2
So you will get [1 – tan Ø 1 * tanØ 2] / [1 + tan Ø 1 * tanØ 2] = (1 – k)/(1 + k)

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