題組內容

1. 設 f (x,y)=xy, x(t)=cost , y(t)=sint, g(t)=f(x(t),y(t)), t∈(-∞,∞ )

(i) (the gradient vector field of f ) 64ba2d7d62b00.jpg?畫幾條 f 的等高線與一些在其上之64ba2d925e4e7.jpg.