3х²+3х-6=0
D= 9+72=81
х₁=(-3+9)/6 =1
х₂= (-3-9)/6=-2
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3</span>*(х-1)*(х-(-2))=(3х-3)(х+2)=3х²-3х+6х-6=3х²+3х-6
3х²+3х-6=<span>(3х-3)(х+2)</span>
√3 - √6 * cos x = 0
√6 * cos x = √3
cos x = √3 / √6
cos x = √(3/6)
cos x = √(1/2)
cos x = 1 / √2
x = ± arccos 1/√2 + 2pi n, n e Z
x= ± pi/4 + 2pi n, n e Z
Ctgx +1/sin²x=3/ctgx/
1/sin²x=ctg²x+1
ctg²x+ctgx+1=3/ctgx/
1)ctgx<0⇒x∈(π/2;π)
ctg²x+ctgx+1=-3ctgx
ctg²x+4ctgx+1=0
ctgx=a
a²+4a+1=0
D=16-4=12
a1=-2-√2⇒ctgx=-2-√2⇒x=-arcctg(2+√2)+πn
a2=-2+√2⇒ctgx=-2+√2⇒x=arcctg(-2+√2)+πn
2)ctgx≥0⇒x∈(0;π/2]
ctg²x+ctgx+1=3ctgx
ctg²x-2ctgx+1=0
(ctgx-1)²=0
ctgx=1⇒x=π/4
4xy(2x+0,5y-xy) = 8х²у + 2ху² - 4х² у²
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