Предмет: Геометрия, автор: shkatena15

В треугольнике АВС угол В равен 120 градусов , АВ = 3. ВС=5. Найдите сторону АС.

Ответы

Автор ответа: dbrnjhbzo

AC²=BC²+AB²-2AB*BC*cos120
AC=25+9-2*3*5*(-0,5)=34+15=49
AC=7

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