(a/(b²-ab)+b/(a²-ab))*ab/(b+a)= (a/(b(b-a))+b/(a(a-b)))*ab/(b+a)= ((a²- b²)/ab(b-a))*ab/(b+a)= (-(a+b)/ab)*ab/(b+a)=-1
3х^2 = 0
x^2 = 0:3
x^2 = 0
x = 0
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3*(-4)+b*6=12
-12+6b=12
6b=12+12
6b=24
b=4
3*(-4)+4*6=12
-12+24=12
примерно так. в конце 4cos^2 x-3/2cos^2 x+1