( ( Х + 1 ) / 2 ) - 3 = ( Х - 1 ) / 3
3( Х + 1 ) - 3•6 = 2( Х - 1 )
3х + 3 - 18 = 2х - 2
3х - 2х = - 2 + 15
Х = 13
-0,7*10000-8*100-26 = -7000-800-26 = -7826
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4 - 9(4 - 20х + 25х^2) = 0
4 - 36 + 180х - 225х^2 = 0
- 225х^2 + 180х - 32 = 0, k = 90
D = k^2 - ac = 8100 - 225* 32 = 900 = 30^2 => D > 0 => уравнение имеет два корня
x1 = (-k + sqrt (D)) / a = (-90 + 30)/(-225) = -60/-225 = 4/15
x2 = (-k - sqrt (D)) / a = (-90 - 30)/(-225) = -120/-225 = 8/15
(4a²b)(7-3a²+5ab-2ab²)=28a²b-12a⁴b+20a³b²-8a³b³
(3-3a²+5ab-12ab²)(-3ab)=-9ab+9a³b-15a²b²+36a²b³