Предмет: Геометрия, автор: irinatolkacheva

В треугольнике АБС угол С равен 90 градусов, соsБ = 5/13,АБ=39. Найдите АС

Ответы

Автор ответа: didenkolga1967

cosB=5/13=CB/AB
т.е. СВ=5 AB=13 По теореме Пифагора найдем AC^2=AB^2-CB^2

AC=12

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