<span>
(n-5m)=4m³n
(a-1)(a²+a+1)=
(a+b)(2a-3b)=2a²-3ab+2ab-3b²=2a²-ab-3b²
(2b+c)(c-2b)=-(c-2b)(c-2b)=-(c²-4b²)
<span>(6-5m)²</span></span>=36-60m+25m²
5X² + 1 = 0; 5X² = - 1; X² = - 1/5 - решений нет.
3-5х>0
x<3/5
*******************************************
y+3/y-3 - y-3/y+3 = 1,5
(y+3)^2 - (y-3)^2 / (y-3)(y+3) = 1,5
y^2 + 6y + 9 - y^2 + 6y - 9 / (y-3)(y+3) = 1,5
12y / y^2 - 9 = 1,5
1,5(y^2 - 9) = 12y
1,5y^2 - 13,5 - 12y = 0
D = (-12)^2 - 4 * 1,5 * (-13,5)
D = 225
y1 = - (-12) + 15 / 2*1,5 = 9
y2 = - (-12) - 15 / 2*1,5 = - 1
ответ: 9, -1