x^4-6x^3+9x^2=0
(x²)(x²-6x+9)=0
(x²)(x-3)²=0
x=0 ou x=3
18x²-2+(2x-1)(3x+1)=0
2(3x-1)(3x+1)+(2x-1)(3x+1)=0
(3x+1)(8x-3)=0
x=-1/3 ou x=3/8
3/2x-2/3x-5/6x=0
9x-4x-5x=0
tout x réel est sol
3/4(x+1)-2/5(x-1)+2=0
15(x+1)-8(x-1)+40=0
7x+63=0
x=-9
1/5(2x5)-x-3-7/5=0
2x-5-5x-15-7=0
-3x-27=0
x=-9
