If cos 55° and sin 55° = 0.8 each then answer of cos 125° + 5 sin 55° is
A). 0.8
B). 2.4
C). 2.8
D). 3.2
Considering Cosine rule, cos C is equal to
A). a² - b² - c²2bc
B). a² + b² - c²2ab
C). 2a + 2b - 2c2ac
D). 2a² + 2b² + 2c²2abc
Formula for area of a triangle ABC is
A). 2ab sin C = 2bc sin A = 2ac sin B
B). 3/2ab sin C = 3/2bc sin A = 3/2ac sin B
C). 1/2ab sin C + 1/2bc sin A + 1/2ac sin B
D). 1/2ab sin C = 1/2bc sin A = 1/2ac sin B
Considering 0° < x < 180°, angle of sin x = 0.2385 is
A). 13.80° , 166.20°
B). 14° , 150°
C). 18.02° , 165.02°
D). 21° , 170.32°
Cosine Rule is also known as
A). Cosine Area
B). Sine triangle
C). Cosine Triangle
D). Cosine Formula