<span>sin(π/2+2x)ctg3x+sin(π+2x)-√2cos5x=0
cos2x *cos3x/sin3x -sin2x-√2cos5x=0
(cos2xcos3x-sin2xsin3x-√2cos5xsin3x)/sin3x=0
</span><span>cos2xcos3x-sin2xsin3x-√2cos5xsin3x=0 U sin3x≠0
cos(3x+2x)-</span>√2cos5xsin3x=0
cos5x-<span>√2cos5xsin3x=0
cos5x(1-√2sin3x)=0
cos5x=0⇒5x=π/2+πn⇒x=π/10+πn/5
sin3x=1/√2⇒3x=(-1)^n *π/4+πn⇒x=</span><span>(-1)^n *π/12+πn</span>/3
1)а-(а-(2а-4))=а-(а-2а+4)=а-а+2а-4=2а-4
2)7х-((y-x)+3)=7x-(y-x+3)=7x-y+x-3=8x-y-3
3)4y+(3x-(2y-(y+1)))=4y+(3x-(2y-y-1))=4y+(3x-2y+y+1)=4y+3x-2y+y+1=3y+3x+1
4)5с-(2с-(b-с))=5с-(2с-b+с)=5с-2с+b-с=2c+b
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