________________________$_____
5*sin(x)+6*sin(2*x)+5*sin(3*x)+sin(4*x)=0; 10*sin(2*x)*cos(x)+6*sin(2*x)+2*sin(2*x)*cos(2*x)=0;
2*sin(2*x)*(5*cos(x)+3+cos(2*x))=0; 1); sin(2*x1)=0;
<span>2). 5*cos(x)+3+cos(2*x)=0; 2*(cos(x))^2+5*cos(x)+2=0; cos(x2)=-0,5;</span>
1089=33*33=1089
121=11*11=121
64=8*8=64
72.25=8,5*8,5=72.25
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9/5.5-7/11=90/55-7/11=90/55-35/55=55/55=1