Question

Помогиттеее, срочнноо!!! Спростіть вираз 3,4

Answer 1

Ответ:

Объяснение:

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Answer 2

$3)(tg\alpha\cos\alpha)^2+(\frac{\sin\alpha}{tg\alpha})=(\frac{\sin\alpha}{\cos\alpha}\cdot \cos\alpha)^2+(\frac{\sin\alpha}{\frac{\sin\alpha}{\cos\alpha}})^2=\sin^2\alpha+\cos^2\alpha=1\\4)\frac{\sin^2\alpha tg^2\alpha}{tg^2\alpha+\cos^2\alpha-1}=\frac{(\sin\alpha tg\alpha)^2}{(\frac{\sin\alpha}{\cos\alpha})^2-(1-\cos^2\alpha)}=\frac{(\sin\alpha\cdot\frac{\sin\alpha}{\cos\alpha})^2}{\frac{\sin^2\alpha}{\cos^2\alpha}}-\sin^2\alpha=$
$\frac{(\frac{\sin^2\alpha}{\cos\alpha})^2}{\frac{\sin^2\alpha-\cos^2\alpha\sin^2\alpha}{\cos^2\alpha}}=\frac{\frac{\sin^4\alpha}{\cos^2\alpha}}{\frac{(1-\cos^2\alpha)\cdot\sin^2\alpha}{\cos^2\alpha}}=\frac{\frac{\sin^4\alpha}{\cos^2\alpha}}{\frac{\sin^2\alpha \sin^2\alpha}{\cos^2\alpha}}=\frac{\frac{\sin^4\alpha}{\cos^2\alpha}}{\frac{\sin^4\alpha}{\cos^2\alpha}}=1$