2 1/12*(-0,8)=25/12*(-8/10)=-10/6=-5/3=-1 2/3
Решение в приложении. Ответ: Алькаши
(x+1)*(x+2) = x^2 +3x+2;
(x-1)*(x+4) = x^2+3x - 4;
x^2 + 3x = y;
(6/(y+2)) + (8/(y-4)) = 1;
y не=-2 и y не=4;
6*(y-4) + 8*(y+2) = (y+2)*(y-4);
6y-24 + 8y +16 = y^2 - 2y -8;
y^2 -y*(2+8+6) - 8 + 24 -16 = 0;
y^2 - 16y =0;
y*(y-16) = 0;
y=0 или y-16=0;
1) y=0; <=> x^2+3x = 0; <=> x*(x+3) = 0; <=> x1=0; или x2=-3.
2) y-16 = 0; <=> x^2+3x - 16 = 0;
D = 3^2 + 4*16 = 9+64 = 73;
x3 = (-3+(V73))/2;
x4 = (-3-(V73))/2.
2x+x+1=34
3x=34-1
3x=33
x=11
1) 5/6 - 1/4 = 20-6/24 = 14/24 = 7/12
2) 8/9 * 3/4 = 2/3
3) 2/3 - 7/12 = 8-7/12 = 1/12