Question

MATLAB求解方程组

x^2+y^2=1
xy=2

%ex_20.m
function z=ex_20(p)
z(1)=p(1)^2+p(2)^2;
z(2)=p(1)*p(2);

保存，然后输入
fsolve x=('ex_20',[0 0])

这样对吗？
错了，保存后输入

x=fsolve('ex_20',[0 0])

Answer 1

>> [x,y]=solve('x^2+y^2=1','x*y=2','x','y')

x =

((15^(1/2)*i)/2 + 1/2)^(1/2)/2 - ((15^(1/2)*i)/2 + 1/2)^(3/2)/2
((15^(1/2)*i)/2 + 1/2)^(3/2)/2 - ((15^(1/2)*i)/2 + 1/2)^(1/2)/2
(1/2 - (15^(1/2)*i)/2)^(1/2)/2 - (1/2 - (15^(1/2)*i)/2)^(3/2)/2
(1/2 - (15^(1/2)*i)/2)^(3/2)/2 - (1/2 - (15^(1/2)*i)/2)^(1/2)/2

y =

((15^(1/2)*i)/2 + 1/2)^(1/2)
-(1/2*15^(1/2)*i + 1/2)^(1/2)
(1/2 - (15^(1/2)*i)/2)^(1/2)
-(1/2 - 1/2*15^(1/2)*i)^(1/2)

>> x=vpa(x)

x =

1.1180339887498948482045868343656 - 0.86602540378443864676372317075294*i
0.86602540378443864676372317075294*i - 1.1180339887498948482045868343656
0.86602540378443864676372317075294*i + 1.1180339887498948482045868343656
- 0.86602540378443864676372317075294*i - 1.1180339887498948482045868343656

>> y=vpa(y)

y =

0.86602540378443864676372317075294*i + 1.1180339887498948482045868343656
- 0.86602540378443864676372317075294*i - 1.1180339887498948482045868343656
1.1180339887498948482045868343656 - 0.86602540378443864676372317075294*i
0.86602540378443864676372317075294*i - 1.1180339887498948482045868343656

>> ex_20([1 1])

ans =

2 1