Предмет: Геометрия, автор: АнюткаХижняк

найдите площадь прямоугольника,если диагональ 10 корень з 3 и угол 30 градусов

Ответы

Автор ответа: Аноним
0
d=10√3
< =30 градусов
стороны
a = d*sin< 
b = d*cos<
^ - степень
площадь S = ab = 
d*sin< *d*cos< =d^2 *1/2 *sin2< = (10√3)^2 *1/2 * sin(2*30)=
                  = 300 *1/2 * sin(60)= 150 *√3/2 =75√3
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