L1=√((X1-X)^2+(Y1-Y)^2+(Z1-Z)^2 ) L2=√((X-X2)^2+(Y-Y2)^2+(Z-Z2)^2 ) X,Y是未知数,其它的都是已知数.如何计算出X,

L1=√((X1-X)^2+(Y1-Y)^2+(Z1-Z)^2 )
L1^2=(X1-X)^2+(Y1-Y)^2+(Z1-Z)^2
(X-X1)^2+(Y-Y1)^2=(Z1-Z)^2-L1^2——(1)
L2=√((X-X2)^2+(Y-Y2)^2+(Z-Z2)^2 )
L2^2=(X-X2)^2+(Y-Y2)^2+(Z-Z2)^2
(X-X2)^2+(Y-Y2)^2=(Z-Z2)^2-L2^2——(2)
(1):X^2-2X1X+X1^2+Y^2-2Y1Y+Y1^2=(Z1-Z)^2-L1^2——(3)
(2):X^2-2X2X+X2^2+Y^2-2Y2Y+Y2^2=(Z2-Z)^2-L2^2——(4)
(3)-(4):
2X2X-2X1X+X1^2-X2^2+2Y2Y-2Y1Y+Y1^2-Y2^2=(Z1-Z)^2-(Z2-Z)^2+L2^2-L1^
(2X2-2X1)X+X1^2-X2^2+(2Y2-2Y1)Y+Y1^2-Y2^2=(Z1-Z)^2-(Z2-Z)^2+L2^2-L1^
(2X2-2X1)X=(Z1-Z)^2-(Z2-Z)^2+L2^2-L1^-X1^2+X2^2-(2Y2-2Y1)Y-Y1^2+Y2^2
X=[Z1-Z)^2-(Z2-Z)^2+L2^2-L1^-X1^2+X2^2-(2Y2-2Y1)Y-Y1^2+Y2^2]/(2X2-2X1)
代入(3)
解方程
把数字代进去,后面就你自己做吧