三角恆等式 | More Trigonometric Identities

[@IDENTITYHK]

IDENTITY 網站： project-identity.hk 影片內容： 00:05 - 三角恆等式 | more trigonometric identities 11:18 - 用 CAST 圖記三角恆等式 | memorizing trigonometric identities using CAST diagram 16:15 - 例子 1 | example 1 19:11 - 例子 2 | example 2 Playlist： HKDSE Maths | 續三角比 | More about Trigonometric Ratios kzbin.info/aero/PL1Pv0-rhcQx6bH3AYTdc-wN143DjIJhYK

[@hkboi7433]

4:16 tbh I think that the proof is the key to understand the entire concept, that's how we could do the questions more easily. It'll be better to put more emphasis on this. Anyways, thanks for making me understand this topic deeply.

[@wolfunnamed4153]

把聲好聽

[@千羽樱]

1-tanx/1+tanx =tanx好似5係否恆等，我試x=22.5係ok架，其實有冇公式計 1-tanx/1+tanx 架

[@IDENTITYHK]

(1 - tan x)/(1 + tan x) 唔等於 tan x 呀，22.5° 係咁啱㗎咋。點解會突登問佢有冇公式計呢？

[@千羽樱]

IDENTITY HK 書度有一題係 tanx=1-tan22.5/1+tan22.5 Ans is x=22.5, 覺得好巧合，唔知係咪有公式。

[@IDENTITYHK]

我喺 IDENTITY 度答咗啲嘢，你睇下明唔明。 project-identity.hk/4-more-trigonometric-identities-三角恆等式/

[@好運來-e7p]

謝謝☺

[@PeachandMario]

TRIGONOMETRY

[@tyovery]

講真呢D式全部唔洗背，諗個十字出黎即刻可以推到，我連ASTC都完全唔會教。 不過教學片永遠都有參考價值。

[@chandanny9521]

簡單啫！

[@mailblack3080]

廢話耶，你只是重複書的内容，真的是廢片

[@corayip4683]

你唔好話你自己蠢 聽唔明😂

[@user-ku2ph6sb4v]

@@corayip4683 sls

[@Max-rt8kz]

收皮啦

[@_sob9254]

那你还想怎样，这是数学，不是文科