Здесь получается формула сокращенного умножения a²-b²=(a-b) (a+b)
(2a-1-a-2)(2a-1+a+2)=(a-3)(3a+1)
2.
х²-11х+24>0
(x-8)(x-3)>0
x∈(3;8)
4.
3-2x>5
(x-2)(x+2)≥0
2x< -2
(x-2)(x+2)≥0
x< -1
x∈(-∞; -2]∪[2;+∞)
x∈(-∞; -1)
x∈(-∞; -2]∪[2;+∞)
x∈(-∞; -1)∪[2;+∞)
1/sinx + 1/cos(7π/2 + x)=2
1/sinx + 1/cos(3π/2+2π+x)=2
1/sinx +1/cos(3π/2+x)=2
1/snx + 1/cos(π/2+π+x)=2
1/sinx + 1/(-cos(π/2+x))=2
1/sinx +1/sinx=2
2/sinx=2sinx | *(1/2 *sinx);sinx≠0
sin^2 x=1
|sinx|=1
sinx=-1 ili sinx=1
x=-π/2+2πn x=π/2+2πn
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x⊂[-5π/2; -π]
-5π/2 ≤-π/2+2πn≤-π -5π/2≤π/2+2πn≤-π
-5π/2+π/2≤2πn≤-π+π/2 -3π/(2π)≤n≤ -π/(2π)
-4π/2≤2πn≤-π/2 -1,5≤n≤ -1/2 ; n-celoe
(-2π)/(2π)≤n≤-π/(2*2π); n=-1
-1≤n≤-1/4 x=π/2-2π; x=-3π/4
n=-1 -----------
n=-1; -π/2-2π=-5π/2
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1. 2sin3x*cos3x=минус корень из 3/2
sin6x=-√3/2
6x=(-1)^(n+1)П/3+Пn
x=(-1)^(n+1)П/18+Пn/3 n∈Z
2.sin^2 3x=3/4
cos^23x=1-3/4=1/4
cos3x=1/2
3x=+-П/3+2Пk
x=+-П/9+2Пk/3
cos3x=-1/2
3x=+-2П/3+2Пk
x=+-2П/9+2Пk/3 k∈Z