Question

prove that sec2A-tan2A = cot A+1/ cot A-1
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Answer 1

Step-by-step explanation:

sec2A - tan2A = cot A+1/ cot A-1

LHS = sec2A - tan2A =2, by using identity , 1+tan2A=sec2A,sec2A-tan2A =1.

LHS =1

RHS=cot A+1/cot A-1

cot A+1=cosA+1/sinA+1

cot A-1=cosA-1/sinA-1

cot A+1/cot A-1= cosA+1/sinA+1 *sinA-1/cosA-1

= -1/-1=1

LHS=RHS

hence proved that sec2A-tan2A=cot A+1/cot A-1.