2(3x-1)-3(x-1)=x+7
(1) x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8
2x²+7x+1=0 x(x-1)=3x+7
1/x-2=7x/(x-2) -3
解方程:(2x-3)(x+1)-x(x-7)=(x-3)(x+2)
方程 3x(7-2x)+5x(2x-1)=4x(x-3)+56
(1)6+2(x-3)=X (2)8-2(x-7)=x-(x-4) (3)2x-(1.5x-1)=2(1.5x-1)
求和:Sn=1+3x+5x*x+7x*x*x+……+(2n-1)x^n-1 (x不为0和1)
x+1分之x+2减去x+3分之x+4=x+5分之x+6减去X+7分之x+8 (解方程)
x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x
[x(x+1)+x平方(x-1)]+(-3x)
(x-1)^3(x+1)(x-2)/(x+4)
(x+1)(x+2)(x+3)(x+4)+1