2/(x+y)+5/(x-y)=-8,9/(x+y)-10/(x-y)=-11 他舅近来帮忙下
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2/(x+y)+5/(x-y)=-8,9/(x+y)-10/(x-y)=-11 他舅近来帮忙下
2/(x+y)+5/(x-y)=-8,9/(x+y)-10/(x-y)=-11 他舅近来帮忙下
2/(x+y)+5/(x-y)=-8,9/(x+y)-10/(x-y)=-11 他舅近来帮忙下
1/(x+y)=a
1/(x-y)=b
则2a+5b=-8 (1)
9a-10b=-11 (2)
(1)*2+(2)
13a=-27
a=-27/13
b=-1194/65
所以
x+y=-13/27
x-y=-65/1194
相加,求出x
相减,求出y
设a=1/(x+y),b=1/(x-y),则得:
2a+5b=-8,9a-10b=-11, 解之得:
a=-27/13,b=-50/13
则:a=1/(x+y)= -27/13,b=1/(x-y)= -50/13,得由a,b 得:
x+y= -13/27, x-y= -13/50 解之得:
x= -1001/6...
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设a=1/(x+y),b=1/(x-y),则得:
2a+5b=-8,9a-10b=-11, 解之得:
a=-27/13,b=-50/13
则:a=1/(x+y)= -27/13,b=1/(x-y)= -50/13,得由a,b 得:
x+y= -13/27, x-y= -13/50 解之得:
x= -1001/675, y= -2353/1350
可能结果计算错了,望楼主核实,方法应该是这样的,谢谢~~
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1/(x+y)=a
1/(x-y)=b
则2a+5b=-8 (1)
9a-10b=-11 (2)
(1)*2+(2)
13a=-27
a=-27/13
b=-10/13
所以
x+y=-13/27
x-y=-13/10
相加,求出x=-481/540
相减,求出y =221/540