Question

Вирішати 1 приклад....​

Answer 1

$\displaystyle\bf\\\frac{1-Sin^{4} \alpha -Cos^{4} \alpha }{Sin^{2}\alpha \cdot Cos^{2} \alpha } =\frac{Sin^{2}\alpha +Cos^{2} \alpha -Sin^{4} \alpha -Cos^{4} \alpha }{Sin^{2}\alpha \cdot Cos^{2} \alpha } =\\\\\\=\frac{(Sin^{2}\alpha -Sin^{4} \alpha)+(Cos^{2}\alpha -Cos^{4} \alpha) }{Sin^{2}\alpha \cdot Cos^{2} \alpha } =\\\\\\=\frac{Sin^{2} \alpha \cdot(1-Sin^{2} \alpha )+Cos^{2}\alpha \cdot(1-Cos^{2}\alpha ) }{Sin^{2} \alpha \cdot Cos^{2} \alpha } =$

$\displaystyle\bf\\=\frac{Sin^{2} \alpha \cdot Cos^{2} \alpha +Cos^{2}\alpha \cdot Sin^{2} \alpha }{Sin^{2} \alpha \cdot Cos^{2} \alpha } =\frac{2Sin^{2} \alpha Cos^{2}\alpha }{Sin^{2}\alpha Cos^{2} \alpha } =2$