Sina*cosa/tga+ctga-sin2a*cos2a

Question

Sina*cosa/tga+ctga-sin2a*cos2a

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Answer 1

Sinacosa/(tga+ctga)-sin²acos²a=sinacosa:(sina/cosa+cosa/sina)-sin²acos²a=
=sinacosa:(sin²a+cos²a)/sinacosa -sin²acos²a=sinacosa:1/sinacosa -sin²acos²a=
=sinacosa * sinacosa -sin²acos²a=sin²acos²a -sin²acos²a=0

Comments

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