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Вова Орлов
Юлия
....
sin^2(x) + cos^2(x) + 2sin(x)cos(x) = 7(sin(x) + cos(x))
(sin(x) + cos(x))^2 - 7(sin(x) + cos(x)) = 0
(sin(x) + cos(x))(sin(x) + cos(x) - 7) = 0
sin(x) + cos(x) = V2sin(x + pi/4) = 0
x + pi/4 = pik
x = pik - pi/4, k E Z
sin(x) + cos(x) - 7 = V2sin(x + pi/4) - 7 != 0, так как |sin(x + pi/4)|
Филюк
Ответ. 1+sin(2*x)=7*(sin(x)+cos(x)); (sin(x)+cos(x))^2-7*(sin(x)+cos(x))=0;
(sin(x)+cos(x))*(sin(x)+cos(x)-7)=0; sin(x)+cos(x)=0; tg(x)=-1;
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