運算式 3: "X" left parenthesis, "t" , right parenthesis equals "f" left parenthesis, "t" , right parenthesis cosine left parenthesis, "t" , right parenthesisXt=ftcost
3
運算式 4: "Y" left parenthesis, "t" , right parenthesis equals "f" left parenthesis, "t" , right parenthesis sine left parenthesis, "t" , right parenthesisYt=ftsint
4
運算式 5: left parenthesis, "X" left parenthesis, "t" , right parenthesis , "Y" left parenthesis, "t" , right parenthesis , right parenthesisXt,Yt
00
定義域 t 最小值：
less than or equal to "t" less than or equal to≤t≤
