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Слева формула корень из (4^2+3^2)sin(x+argtg(3/4))=5; sin(x+argtg(3/4))=1:
x+argtg(3/4)=Пі/2+2Пі*n x=argtg(3/4)+Пі/2+2Пі*n
X^2 - 3X = 0
X * ( X - 3 ) = 0
X = 0
X - 3 = 0 ---> X = 3
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1) X^2 - 3X + 12K = 0
0 ^2 - 3 * 0 + 12K = 0
12K = 0
K = 0
2) X^2 - 3X + 12K = 0
3 ^2 - 3 * 3 + 12K = 0
12K = 0
K = 0
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ОТВЕТ: при К = 0
Cos13п/6=cos390=cos30= (корень из 3 )/2
Х-3(1-7х)+2х+2=0
х-3+21х+2х+2=0
х+21х+2х= -2+3
24х=1
х=1/24