Question

Prove that (1-cos a/1+cos a) + (1+cos a/1-cos a)= 2 + 4 cot^2 a

Answer 1

Answer:

I think you mean to ask:

How do I prove that (1+CosA)(1-CosA)(1+Cot^(2)A)=1

Solution: LHS=(1-Cos^(2)A)(1+Cot^(2)A)

=Sin^(2)A(1+Cos^(2)A/Sin^(2)A)

=(Sin^(2)A)(Sin^(2)A+Cos^(2)A)/Sin^(2)A

=Sin^(2)A(1)/Sin^(2)A=1*1=1

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