Предмет: Геометрия, автор: elinasmirnova

из точки А,лежащей на окружнеости,проведены две хорды,равные радиусу.Вычислите величину полученного вписанного угла А

Ответы

Автор ответа: dtnth
0

Пусть проведены хорды AB и AC, O - центр окружности.

Тогда по условию AB=AC=OA=OB=OC=R

Треугольники ABO, ACO равносторонние(по опрделению)

поєтому угол OAB=угол OAC=60 градусов (по свойству равностороннего треугольника)

угол BAC=угол OAB+угол OAC=60 градусов+60 градусов=120 градусов

Ответ: 120 градусов

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