[考古] 98台聯大

[claudina (claudina)]

What is the area that lies inside the circle r=6 and above the line r=3cscθ?
r=3cscθ這條線怎麼畫?

Let S be the surface parametrized by r(θ,z)=3sin2θi+6sin^2θj+zk where
0<=θ<=π. Which of the following is equivalent to the surface differential
d∂?

這兩題我完全不會算,請給我完整過程,謝謝!

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推 dreamenjoy:第一題 r=3cscθ是y=3 因為r=3 1/sin
→ dreamenjoy:再把sin移項 得y=3
→ dreamenjoy:第二題 用jacobin算 用打的太麻煩了..
→ dreamenjoy:看課本應該有 得出答案是6θ我記得
→ dreamenjoy:就代公式進去
→ dreamenjoy:其實你可以去math版問 這編人比較少
→ dreamenjoy:要問到答案可能比較慢
→ claudina:謝謝,我等很久以為沒人回了