Question

упростите выражение синус 5acos 4a-cos 5asin 4a+sina​

Answer 1

sin5acos4a-cos5asin4a+sina​

sin(5a-4a)+sina

sina+sina

2sina

Answer 2

$Sin5\alpha Cos4\alpha-Cos5\alpha Sin4\alpha+Sin\alpha=Sin(5\alpha-4\alpha)+Sin\alpha =\\\\=Sin\alpha+Sin\alpha=\boxed{2Sin\alpha}$