А) 2*(1+2x+x^2)-4x=2+4x+x^2-4x=2+x^2
б) 2x+4-x^2-2x+x^2+6x+9=6x+13
в) 4y^2+4y+y^4-y^2(y+1-y^2-y)+6y-4y^3=4y^2+4y+y^4-y^2+y^4+6y-4y^3=2y^4-4y^3+3y^2+10y
г) 64-48x+36y^2+48x-36x^2+27x^3-27x^3=64+36y^2-36x^2
Sin(5x-2x)=√2/2
sin3x=√/2
3x=(-1)ⁿ (π/4) + πk
x=(-1)ⁿ (π/12) + (π/3)k, k∈Z.
Странное задание.
{(x+y)•(x ²+y²)²[x•(a-1)+(y-2x+a² x]+y ⁴}•(-2x)==(x+y)(x²+y²)²(ax-<u>x</u>+y-<u>2x</u>+a²x+y⁴)(-2x)=(x+y)(x²+y²)²(-2ax²+6x²-2xy-2a²x²-2xy⁴)
7cos2a= 7-14sin^2(a)= 7-14*0.04=6.44
<span>7c^2 (2c - 9)
=14с³-63с²
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