RE: Mathematical Centre 數學求助中心 做數有唔識歡迎提問
回復 20# chiuandy123sin C = -(sin A + sin B)
cos C = -(cos A + cos B)
sin²C = (sin A + sin B)²
cos²C = (cos A + cos B)²
in terms of? 回復chiuandy123
sin C = -(sin A + sin B)
cos C = -(cos A + cos B)
sin²C = (sin A + sin B)²
c ...
曲奇bb 發表於 1-3-2013 15:51 http://www.nakuz.com/bbs/images/common/back.gif
a) Express sin square C in terms of sinA and sinB
b) Express con square C in terms of cosA and cosB a) Express sin square C in terms of sinA and sinB
b) Express con square C in terms of cosA and ...
chiuandy123 發表於 1-3-2013 15:53 http://www.nakuz.com/bbs/images/common/back.gif
我記得C part 我做過, 係的確需要少少時間... 我記得C part 我做過, 係的確需要少少時間...
曲奇bb 發表於 1-3-2013 16:08 http://www.nakuz.com/bbs/images/common/back.gif
我又唔係才智過人 今朝個fd提吓我先識 本帖最後由 曲奇bb 於 1-3-2013 16:30 編輯
我又唔係才智過人 今朝個fd提吓我先識
chiuandy123 發表於 1-3-2013 16:15 http://www.nakuz.com/bbs/images/common/back.gif
其實因為sin A + sin B + sin C = sin B + sin C + sin A = sin C + sin A + sin B = 0
於是sin A, sin B, sin C 輪換
sin A = sin B = sin C = 0 為其中一解
case 1: A = 2pi, B = pi
case 2: A = 2pi, B = 0
case 3: A = pi, B = 0
我唔知係0\<A, B, C\<2pi 定0\<A, B, C <2pi
係觀察多項式時可以多d 留意下調一調位會唔會可以變返原本個一條式 其實因為sin A + sin B + sin C = sin B + sin C + sin A = sin C + sin A + sin B = 0
於是sin A, ...
曲奇bb 發表於 1-3-2013 16:29 http://www.nakuz.com/bbs/images/common/back.gif
thx 我又唔係才智過人 今朝個fd提吓我先識
chiuandy123 發表於 1-3-2013 16:15 http://www.nakuz.com/bbs/images/common/back.gif
但係let 左sin B 係0 ge 話, sin A = -sin C
這樣 0<sin A\<1, 0 < A \<pi => 0< A - B \< pi
我很久沒做M2了...
真的有點兒生疏了 ；P 之前m2 quiz見到有一條definite in真係坐左係度(如下)
a) evaluate ∫ln(1+x^2 ) dx
b)Let a(n)=1/n^4 Π(k=1,2n) (n^2+k^2)^1/n, where n=1,2,......
evaluate lim (n->∞) a(n) 之前m2 quiz見到有一條definite in真係坐左係度(如下)
a) evaluate ∫ln(1+x^2 ) dx
b)Let a(n ...
kaiziart 發表於 3-3-2013 00:57 http://www.nakuz.com/bbs/images/common/back.gif
小流你想拆我招牌 lol
遲一兩日先幫你諗 lol 指教 ><