What is cos2x?

cos2x is a trigonometric function where x is an angle measured in radians. It is defined as the cosine of twice the angle x. Mathematically, it can be written as cos2x = cos(x + x) = cos(x)cos(x) - sin(x)sin(x) = 2cos^2(x) - 1.

Some properties of cos2x include:

• It is an even function, which means cos2(-x) = cos2(x)
• Its range is between -1 and 1, inclusive
• It has a period of π, which means that cos2(x + π) = cos2(x)
• The maximum value it can reach is 1, which occurs when x is a multiple of π/2
• The minimum value it can reach is -1, which occurs when x is an odd multiple of π/2.