r(t)=[cos(t),sin(t)]
var('x,y')
fr(x,y)=[-y,-x*y]
frt=fr(cos(t),sin(t))
dr=derivative(r,t)
print frt
diff(frt,t)
print r(t)
r(t)=(cos(t),sin(t))
print r(t)
dr=diff(r,t)
print dr
print dr
print frt
fr_dr=frt.dot_product(dr)

sol=integrate(fr_dr,t,0,pi/2)
sol=1/4*3.14-1/3
print sol

Kreyszig-6.1 (last edited 2010-12-16 12:44:41 by 172)