1/﹙2x+3﹚+21/﹙2x³+3x²-2x-3﹚-3/﹙x²-1﹚-1/﹙2x²+5x+3﹚=0

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/09 10:23:21
1/﹙2x+3﹚+21/﹙2x³+3x²-2x-3﹚-3/﹙x²-1﹚-1/﹙2x²+5x+3﹚=0

1/﹙2x+3﹚+21/﹙2x³+3x²-2x-3﹚-3/﹙x²-1﹚-1/﹙2x²+5x+3﹚=0
1/﹙2x+3﹚+21/﹙2x³+3x²-2x-3﹚-3/﹙x²-1﹚-1/﹙2x²+5x+3﹚=0

1/﹙2x+3﹚+21/﹙2x³+3x²-2x-3﹚-3/﹙x²-1﹚-1/﹙2x²+5x+3﹚=0
2x³+3x²-2x-3=x²(2x+3)-(2x+3)=(x²-1)(2x+3)=(x+1)(x-1)(2x+3)
2x²+5x+3=(2x+3)(x+1)
1/﹙2x+3﹚+21/﹙2x³+3x²-2x-3﹚-3/﹙x²-1﹚-1/﹙2x²+5x+3﹚=0
((x²-1)+21-3(2x+3)-(x-1))/(x+1)(x-1)(2x+3)=0
即x²-1+21-6x-9-x+1=0
x²-7x+12=0
(x-3)(x-4)=0
解得x=3或x=4