Question

(sina-cosa)^2-1ctg-sina*cos-2tg^2a

Answer 1

1)(sina-cosa)²-1=sin²a-2sinacosa+cos²a-sin²a-cos²a=-2sinacosa
2)ctga-sina*cosa=cosa/sina -sinacosa=(cosa-sin²acosa)/sina=
=cosa(1-sin²a)/sina=cos³a/sina
3)-2sinacosa*sina/cos³a=-2sin²a/cos²a=-2tg²a
4)-2tg²a-2tg²a=-4tg²a

Answer 2

Как получилось 1-sin^2