问题
解答题
解答下列各题. (1)化简:(
(2)解方程:
(3)请你先将
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答案
(1)原式=
×2x(x+3)-x(x-3) (x+3)(x-3) (x+3)(x-3) x
=2(x+3)-(x-3)
=2x+6-x+3
=x+9;
(2)方程的两边同乘x(x+3),得
x+3=5x,
解得x=
.3 4
检验:把x=
代入x(x+3)≠0.3 4
∴原方程的解为:x=
.3 4
(3)原式=
×x(x-2) x-1 x-1 x
=x-2,
∵x≠0,1,
∴取x=2,
∴原式=x-2=2-2=0.