Question

sin2a+cos2a×ctga
Упростить вырожение

Answer 1

$sin2a+cos2a*ctga=2sinacosa+(cos^2a-sin^2a)*frac{cosa}{sina}=\2sinacosa+frac{cos^3a}{sina}-sinacosa=sinacosa+frac{cos^3a}{sina}=frac{sin^2acosa+cos^3a}{sina}=\frac{cosa(sin^2a+cos^2a)}{sina}=frac{cosa}{sina}=ctga.$