Предмет: Алгебра, автор: yekaterinamostovaya

ctgx+sinx/(1+cosx)=2

Ответы

Автор ответа: sedinalana

cosx/sinx+sinx/(1+cosx)=2
cosx+cos²x+sin²x=2sinx(1+2cosx),sinx≠0 ,cosx≠-1
1+cosx-2sinx(1+cosx)=0
(1+cosx)(1-2sinx)=0
1+cosx=0⇒cosx=-1 не удов усл
sinx=1/2
x=(-1)^n*π/6+πk,k∈z

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