X/(X-1)=(X+2)/(X-1)
X=幾多??
另外
X/(X-1)=0
X=幾多?
仲有,咁
X*(X-1)=(X+5)*(X-1)
X=幾多?
更新1:
老友~X/(X-1)=(X+2)/(X-1) 交叉相乘 X(X-1)=(X+2)(X-1) X^2-X = X^2+X-2 -2X=-2 X=1 分母可以等於0嗎?
更新2:
must be negative姐係點解?