{{{id=1|
var('x, y,alpha,beta')
var('xx,yy,a,b')
G = xx^2+a*yy^2+2*b*xx*yy
@interact
def _(alpha=(-3,3), beta=(-3, 3)):
def F(x,y):
return G.subs(xx=x).subs(yy=y).subs(a=alpha).subs(b=beta)
plotF=plot3d(F, (-2, 2), (-2, 2), adaptive=True, color='blue')
show(plotF)
///
}}}
{{{id=5|
var ('x y z')
mu=0.0
S1=implicit_plot3d(x^2+y^2==z^2, (x,-2,2), (y,-2,2), (z,-2,2),color=(0,.6,0))
S2=implicit_plot3d(1+mu*x==z, (x,-2,2), (y,-2,2), (z,-2,2),color=(0.6,0.6,0), opacity=0.7)
show(S1+S2, figsize=6, aspect_ratio=[1,1,1])
///
}}}
{{{id=6|
var ('x y')
implicit_plot(x^2-y^3==0, (x,-2,2), (y,-2,2), figsize=4, axes="true" )
///
}}}
{{{id=7|
var ('x y')
implicit_plot(x^2+2*y^2==1, (x,-1,1), (y,-1,1), figsize=4, axes="true" )
///
}}}
{{{id=8|
var ('x y')
implicit_plot(x+y+x^2*y==0, (x,-5,5), (y,-1,1), figsize=4, axes="true" )
///
}}}
{{{id=9|
var ('x y')
implicit_plot(x^3+y^3-3*x*y==0, (x,-3,3), (y,-3,3), figsize=4, axes="true" )
///
}}}
{{{id=10|
var('x,y')
utility=implicit_plot(10*x^0.6*y^0.4==10*18^0.6*8^0.4, (x,0,40),(y,0,40),axes="true")
budget=implicit_plot(20*x+30*y==600,(x,0,40),(y,0,40),axes="true",color='red')
plot(utility+budget)
///
}}}
{{{id=11|
///
}}}