Question

$\cot( \alpha ) \times \tan( \alpha ) + \cot( ^{2} ) \alpha =$ ?
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Answer 1

Ответ:

$\frac{1}{sin^{2} \alpha}$

Пошаговое объяснение:

$ctg\alpha *tg\alpha +ctg^{2} \alpha =\frac{cos\alpha }{sin\alpha } *\frac{sin\alpha }{cos\alpha } +\frac{cos^{2} \alpha}{sin^{2} \alpha} =\\=1++\frac{cos^{2} \alpha}{sin^{2} \alpha} =\frac{sin^{2} \alpha+cos^{2} \alpha}{sin^{2} \alpha}=\frac{1}{sin^{2} \alpha}$