1.如果A,B都是实数,且总有A/(x-5)+B/(x+2)=(5x-4)/(x²-3x-10),则A=____,B=____.【填空,2.分式(x+3)/(x²-x-12)的值能等于0吗?请说明理由
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![1.如果A,B都是实数,且总有A/(x-5)+B/(x+2)=(5x-4)/(x²-3x-10),则A=____,B=____.【填空,2.分式(x+3)/(x²-x-12)的值能等于0吗?请说明理由](/uploads/image/z/1721404-28-4.jpg?t=1.%E5%A6%82%E6%9E%9CA%2CB%E9%83%BD%E6%98%AF%E5%AE%9E%E6%95%B0%2C%E4%B8%94%E6%80%BB%E6%9C%89A%2F%28x-5%29%2BB%2F%28x%2B2%29%3D%285x-4%29%2F%28x%26%23178%3B-3x-10%29%2C%E5%88%99A%3D____%2CB%3D____.%E3%80%90%E5%A1%AB%E7%A9%BA%2C2.%E5%88%86%E5%BC%8F%EF%BC%88x%2B3%29%2F%28x%26%23178%3B-x-12%29%E7%9A%84%E5%80%BC%E8%83%BD%E7%AD%89%E4%BA%8E0%E5%90%97%3F%E8%AF%B7%E8%AF%B4%E6%98%8E%E7%90%86%E7%94%B1)
1.如果A,B都是实数,且总有A/(x-5)+B/(x+2)=(5x-4)/(x²-3x-10),则A=____,B=____.【填空,2.分式(x+3)/(x²-x-12)的值能等于0吗?请说明理由
1.如果A,B都是实数,且总有A/(x-5)+B/(x+2)=(5x-4)/(x²-3x-10),则A=____,B=____.【填空,
2.分式(x+3)/(x²-x-12)的值能等于0吗?请说明理由
1.如果A,B都是实数,且总有A/(x-5)+B/(x+2)=(5x-4)/(x²-3x-10),则A=____,B=____.【填空,2.分式(x+3)/(x²-x-12)的值能等于0吗?请说明理由
如果A,B都是实数,且总有A/(x-5)+B/(x+2)=(5x-4)/(x²-3x-10),则A=_7___,B=___-2_.【填空,
分式(x+3)/(x²-x-12)的值能等于0吗?请说明理由
不能,因为如果它=0
那么x+3=0,x=-3
此时x²-x-12=9+3-12=0分式没有意义
(1)A=7 ,B=-2
(2)(x+3)/(x²-x-12) =(x+3)/[(x+3)(x-4)]
若要使原式为0, 则x+3=0此时分母也为0分式无意义,所以分式(x+3)/(x²-x-12)的值不能等于0
a=3 b=2 (x+3)/(x²-x-12) 分式有意义,则x²-x-12不等于0 即是x不等于4或x不等于-3 所以分式的值不能等于0
1、A(x+2)+B(x-5)=(A+B)x+2A-5B=5x-4
即A+B=5,2A-5B=-4,故A=3,B=2
2、不能,若分数值为0,则x=-3,此时分母为0,无意义