By formula,
cosec2 A - cot2 A = 1
Solving L.H.S. of the equation :
⇒sec A (cosec A - cot A)(cosec A - cot A)2+1⇒sec A (cosec A - cot A)(cosec A - cot A)2+cosec2A−cot2A⇒sec A (cosec A - cot A)(cosec A - cot A)2+(cosec A - cot A)(cosec A + cot A)⇒sec A (cosec A - cot A)(cosec A - cot A)(cosec A - cot A + cosec A + cot A)⇒sec A2 cosec A⇒cos A1sin A2⇒sin A2 cos A⇒2 cot A.
Since, L.H.S. = R.H.S.
Hence, proved that sec A (cosec A - cot A)(cosec A - cot A)2+1=2 cot A.