使分式﹙2x²-5x-12﹚/﹙x²-x-12﹚的值为零的x的值是

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使分式﹙2x²-5x-12﹚/﹙x²-x-12﹚的值为零的x的值是

使分式﹙2x²-5x-12﹚/﹙x²-x-12﹚的值为零的x的值是
使分式﹙2x²-5x-12﹚/﹙x²-x-12﹚的值为零的x的值是

使分式﹙2x²-5x-12﹚/﹙x²-x-12﹚的值为零的x的值是
﹙2x²-5x-12﹚/﹙x²-x-12﹚的值为零
所以 2x²-5x-12=0 且x²-x-12≠0
解 2x²-5x-12=0 得
(2x+3)(x-4)=0 得 x=-3/2 或 x=4
解 x²-x-12≠0
得 (x-4)(x+3)≠0 得 x≠-3 或 x≠4
综上得 x=-3/2

﹙2x²-5x-12﹚/﹙x²-x-12﹚=(2x+3)(x-4)/[(x-4)(x+3)]
x=-3/2,
x≠4,
∴x=-3/2.

﹙2x²-5x-12﹚/﹙x²-x-12﹚=0
则2x²-5x-12=0
(x-4)*(2x+3)=0
x=4或-3/2
但是当x=4时﹙x²-x-12﹚=0此时分式无意思
故x=-3/2

﹙2x²-5x-12﹚/﹙x²-x-12﹚=0
2x²-5x-12=0且x²-x-12≠0
解得
x=-3/2