일반수학및실습2-12.7절

2127 days 전, jhlee2chn 작성

예.

var('x, y') f(x, y)=3*x^3+y^2-9*x+4*y fx=diff(f, x);fy=diff(f, y) solve([fx==0, fy==0], x, y) 
       
[[x == 1, y == -2], [x == -1, y == -2]]
[[x == 1, y == -2], [x == -1, y == -2]]
fxx=diff(fx, x);fxy=diff(fx, y);fyy=diff(fy, y) A=fxx(1, -2);B=fxy(1, -2);C=fyy(1, -2);D=A*C-B^2 print A, B, C, D 
       
18 0 2 36
18 0 2 36
A=fxx(-1, -2);B=fxy(-1, -2);C=fyy(-1, -2);D=A*C-B^2 print A, B, C, D 
       
-18 0 2 -36
-18 0 2 -36