1) 6\(x+1)(x+2)+8\(x-1)(x+4)=1
2) x\x-3+4\x+3=18\x^2-9
3)15- (2x-4-3x\5)=7x- x-7\2-5x
4)x^6-19x^3-216=0
5)x^4-y^4\4x^2-2x+y-y^2:x^3-x^2y+xy^2-y^3\2x-y

V-это корень1)(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))/2.2)на фотону наверное так