1) 64m^3 -1 = (4m)^3 - 1^3 = (4m - 1)*(16m^2 + 4m + 1)
По теореме виета x1+x2=-b/a
-4+3=-1 p=1
1)<span>7 - х/2 = 3 + 7х/2
7-x=3+7x
7x+x=7-3
8x=4
x=0,5
2)9 - 2х/3 = 7+ х/3
9-2x=7+x
x+2x=9-7
3x=2
x=2/3
3)х+3/2 = х - 4
x+3=2x-8
2x-x=3+8
x=11
4)2 - 3х = х-12/2</span>
4-6x=x-12
x+6x=4+12
7x=16
x=16/7=2 2/7
Sin15 =sin(45-30) = sin30= 1/2