<span>2 - (1 + 3х)/3 > 1 - (1 - х)/2
12-2-6х>6-3+3x
3x+6x<7
x<7/9
наибольшее целое 0
</span>
Sin^2a + sin^2b + cos(a + b)*cos(a - b) = sin^2a + sin^2b + cos^2a - sin^2b = sin^2a + cos^2a = 1.
5x+4=0
5x=-4
x= - 4/5
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3(3x-2)+2(7x-4)=10-5(3-4x)
9x-6+14x-8=10-15+20x
9x+14x-20x=10+6+8-15
3x=9
x=9/3
x=3
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