This document provides information about trigonometry including definitions of trigonometric ratios, quadrant values, trigonometric identities, and example problems. It begins with definitions of sine, cosine, and tangent ratios. It then covers key topics like trigonometric ratios in each quadrant, trigonometric identities, addition and subtraction formulas, multiplication formulas, and example problems with solutions. The document is a lesson plan on trigonometry concepts and formulas for a high school math class.
6. Contoh Soal
A.Sin 140° = … B.Cos 240° = …
Penyelesaian:
B. Cos 240° = Kuadran III
Cos (18𝟎°+ ∝) = 240°
Cos (1𝟖𝟎° + 𝟔𝟎°) = 240°
∝ = 6𝟎°
Cos 60° =
Penyelesaian:
A. Sin 135° = Kuadran II
Sin (180°− ∝) = 135°
Sin (180° − 𝟒𝟓°) = 135°
∝ = 𝟒𝟎°
Sin 𝟒𝟓° =
16. LATIHAN
SOAL
1. Cos (270°)
2. Sin (204°)
3. Tan (60°)
4. Sec (167°)
5. Sin260°+Cos260°
6. 2. 𝐶𝑜𝑠260°+2. 𝑆𝑖𝑛245+3. 𝑇𝑎𝑛245°
7. Sin 135°
8. Cos(90°-30°)
9. Cos 60°-Cos 30°
10.Jika f(x) = (Cos x + Sin x) . Tentukan nilai f(x),
jika x = 45°
17. PEMBAHASAN
SOAL
1. Cos (270°) = K III
Cos (180°+∝) = 270°
Cos (180°+𝟗𝟎°) = 270°
∝ = 𝟗𝟎°
Cos 𝟗𝟎° = 𝟎
2. Sin (204°) = K III
Sin (180°+∝) = 204°
Sin (180°+𝟐𝟒°) = 204°
∝ = 𝟐𝟒° (−)
3. Tan (60°) = K I
Tan (90°− ∝) = 60°
Tan (90° − 𝟑𝟎°) = 60°
∝ = 𝟑𝟎°
Tan 3𝟎° = 𝟏
𝟑 𝟑
4. Sec (167°) = K II
Sec (180° −∝) = 167°
Sin (180° − 𝟏𝟑°) = 167°
∝ = 𝟏𝟑° (+)