Q5 of 104 Page 196

If A + B = 90, prove that

cos(90–θ ) = sinθ

tan(90–θ ) = cotθ


sin(90–θ ) = cosθ


cot(90–θ ) = tanθ


cosec(90–θ ) = secθ


sec(90–θ) = cosecθ


L.H.S



∵ A + B = 90





∵


= secA


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