Question

Sin3x×sin^2x=sin3xcos^2x Заранее спасибо

Answer 1

$sin3x*sin^2x=sin3x*cos^2x\sin3x*sin^2x-sin3x*cos^2x=0\sin3x(sin^2x-cos^2x)=0\-sin3x(cos^2x-sin^2x)=0\sin3x*cos2x=0\\ left[begin{array}{ccc}sin3x=0\cos2x=0end{array}right= textgreater left[begin{array}{ccc}3x=pi n;nin Z\2x=frac{pi}2+pi n;nin Zend{array}right= textgreater \\= textgreater left[begin{array}{ccc}x=frac{pi n}3;nin Z\x=frac{pi}4+frac{pi n}2;nin Zend{array}right$