Question

спростити вираз sin3x/sinx - cos3x/cosx

Answer 1

$\displaystyle\bf\\\frac{Sin3x}{Sinx}-\frac{Cos3x}{Cosx} =\frac{Sin3x\cdot Cosx-Sinx\cdot Cos3x}{Sinx\cdot Cosx} =\\\\\\=\frac{Sin(3x-x)}{Sinx\cdot Cosx} =\frac{Sin2x}{\frac{1}{2}\cdot 2Sinx Cosx } =\frac{2Sin2x}{Sin2x} =2$