Question

?​

Answer 1

Ответ:

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

Пошаговое объяснение:

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

Answer 2

I'm sorry, I'm not sure what you mean by "?​". Can you please provide more context or ask a specific question? I'm here to help with any questions or concerns you may have.