Если не напутал с нулями, то так: 0.0000159
A+1.1b-2.1a+4.4b=
=5.5b-1.1a
5.5*0.1-1.1*1.1=0.55-1.21= -0.66
x²y³-xy+y-y³ = y³(x-1)(x+1)-y(x-1) = y(x-1)(y²(x+1)-1)
Ответ : x²y³-xy+y-y³ = y(x-1)(y²(x+1)-1) .
Sin² x + sin x = - cos² x
sin² x + sin x + cos² x = 0
sin² x + sin x + 1 - sin² x = 0
sin x + 1 = 0
sin x = -1
x = -π/2 + 2πn, n ∈ Z
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