Cosine 120 equals -½ or -0.5. Trigonometry deals with relationships between angles and sides of right triangles. Right triangle has one 90° angle and two angles less than 90°
Clock has three modes: time, angles, and fractions. Digital clock shows 12/24 hour format with AM/PM. Current time display shows computer's clock. Random time mode generates random clock hands
A 180-degree angle is a straight angle that forms a straight line. It is exactly half of a full angle (360 degrees). The two arms of the angle are opposite from the common vertex. It is also known as a half-circle or semi-circle
Sin3x represents the sine function for an angle that is three times the angle of x. The formula is sin3x = 3 sin x - 4 sin³x. The period of sin³x is 2π/3 radians
A 45-degree angle is half of a 90-degree angle. It is an acute angle formed when two rays meet at a vertex. Two 45-degree angles form a 90-degree right angle
Cos a cos b is a trigonometric identity for two angles. Formula is cos a cos b = (1/2)[cos(a + b) + cos(a - b)]. Formula applies when either angles or their sum/difference are known