-making use of the identities (for proving questions)
-......= x (for proving questions)
x....= 2x
-divide the whole thing by something (for proving questions)
-1/cos²θ=tan²θ+1
-construct a triangle (to find the three sides of the triangle)
-A+B-A = B (for proving questions)
I really have to list it out as I am not able to do the questions intuitively...
Besides, how do you do proving questions on the topic product to sum formulae and sum to product formulae? I find it extremely hard to master.
I am desperate for help!!
Thanks a million!!!!!!!!!!!
更新1:
大家都誤會左 sorry我表達能力有問題 我意思係我做果陣要諗返上面果d 絕對唔會寫返出黎=.= 運用formula/identity我梗係知一定要=.= 所以先放左係個表到既第一點到= = 我覺得我遇到果d題目都係「比較煩」 好似呢題咁 it is given that sinB/sinA = cos(A+B). prove that tan(A+B)=2tanA 果陣岩岩學完老師叫我地做 我做左勁耐都做唔到 個方法其實勁簡單 將個sinB變做sin(A+B-A) 之後加四個steps搞掂 (model ans)
更新2:
我係yahoo知識+搵過 有另外三個唔同既方法 不過呢個最快 五個steps KO PS 我絕對唔係果d見到條題目停左係到唔郁果d人黎 我係想要d快d既方法做
更新3:
原來係兩個 http://hk.knowledge.yahoo.com/question/question?qid=7011052300741 http://hk.knowledge.yahoo.com/question/question?qid=7010020501155 你話上面個方法係咪快= =.. 我係想要呢d方法 唔係想你話我知"做多d就會好d!" 呢樣野係人都知
更新4:
"你地"..
