来自陈朝元的问题
3元1次方程x-2y=-93x-y+z=4{y-z=3{2x+3y-z=122z+x=47x+y+z=6
3元1次方程
x-2y=-93x-y+z=4
{y-z=3{2x+3y-z=12
2z+x=47x+y+z=6
1回答
2020-06-24 21:21
3元1次方程x-2y=-93x-y+z=4{y-z=3{2x+3y-z=122z+x=47x+y+z=6
3元1次方程
x-2y=-93x-y+z=4
{y-z=3{2x+3y-z=12
2z+x=47x+y+z=6
x-2y=-9...(1)y-z=3.(2)2z+x=47.(3)(1)+(2)*2得到:x-2z=-3.(4)(3)+(4)得到:x=22;代入(4)得到:z=25/2;进而可得到:y=31/2;所以第一题:x=45,y=31/2,z=25/2.3x-y+z=4..(1)2x+3y-z=12...(2)x+y+z=6.(3)(1)-(3)可...