Hình 1:
\(\sin\widehat{D}=\dfrac{AC}{DC};\cos\widehat{D}=\dfrac{AD}{DC};\tan\widehat{D}=\dfrac{AC}{AD};\cot\widehat{D}=\dfrac{AD}{AC}\)
Hình 2:
\(\sin\widehat{I}=\dfrac{GH}{GI};\cos\widehat{I}=\dfrac{HI}{GI};\tan\widehat{I}=\dfrac{GH}{HI};\cot\widehat{I}=\dfrac{HI}{GH}\)
Hình 3:
\(\sin\widehat{E}=\dfrac{DF}{ED};\cos\widehat{E}=\dfrac{EF}{ED};\tan\widehat{E}=\dfrac{DF}{EF};\cot\widehat{E}=\dfrac{EF}{DE}\)
Nhóm 1:
SinD = \(\dfrac{AC}{DC}\), CosD = \(\dfrac{AD}{DC}\), TanD = \(\dfrac{AC}{AD}\), CotD = \(\dfrac{AD}{AC}\)
Nhóm 2:
SinI = \(\dfrac{GH}{IG}\), CosI = \(\dfrac{IH}{IG}\), TanI = \(\dfrac{GH}{HI}\), CotI = \(\dfrac{IH}{HG}\)
Nhóm 3:
SinE = \(\dfrac{DF}{DE}\), CosE = \(\dfrac{EF}{DE}\), TanE = \(\dfrac{DF}{EF}\), CotE = \(\dfrac{EF}{DF}\)
