Question

Sinα=7/25;  0<α<$pi$/2 Вычислить
 cos α  tg α ctg α cos$alpha$/2

Answer 1

cosa=$sqrt{1-sin ^{2}x} = sqrt{1- frac{49}{625} } = sqrt{ frac{576}{625} } = frac{24}{25}$

tga=$frac{7}{25}/ frac{24}{25} = frac{7}{24}$
ctga=$frac{1}{tg alpha } = 1/ frac{7}{24}= frac{24}{7}$