cosec (65° + θ) — sec (25° —θ) — tan (55° — θ) + cot (35° + θ) =0

Consider L.H.S.

= cosec (65° + θ) — sec (25° —θ) — tan (55° — θ) + cot (35° + θ)


= cosec (65° + θ) — sec (90° - (65° + θ)) — tan (90° - (35° + θ)) + cot (35° + θ)


= cosec (65° + θ) — cosec (65° + θ)) — cot (35° + θ) + cot (35° + θ)


= 0 = R.H.S.


Hence, proved.


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