Предмет: Математика, автор: ov9282433

Помогите решить уравнение
2cos^2x-2=3sinx​

Ответы

Автор ответа: SomethingMySecrets
0

Пошаговое объяснение:

2cos^2x-2=3sinx => 2cos^2x-3sinx-2=0

2cos^2x=2(1-sin^2x)=2-2sin^2x

Обозначим sinx , буквой t

-2t^2-3t=0

a=-2;b=-3;c=0

D=b^2-4ac => D=9 => √D=3

===================================

t1=(-b+√D):2a => t1=(3+3):(-4)=-1.5 такого не может быть так как границы значения sinx от -1 до 1 .

t2=(-b-√D):2a => t2=(3-3):(-4)=0

Значит:

2)sinx=0

===================================

Если тебе надо найти ещё cos^2x, то:

Cos^2x=1-sin^x= 1-0=1 => cosx=1

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