Question

В треугольнике ABC угол C=90º, BC=10, sinB=2/sqrt(29). Найдите AC.

 

Answer 1

cos^2(B) = 1-sin^2(B) = 1 - 4/29 = 25/29

cosB = 5/sqrt(29)

tgB = sinB/cosB = 2/sqrt(29) : 5/sqrt(29) = 0,4 = AC/BC

AC = 0,4*BC = 4