cos(θ) is the x-coordinate of the point P and, sin(θ) is the y-coordinate of the point P. This applet shows how the graphs of sin(θ) and cos(θ) follow directly from the definition of these functions.

This circle has the centre at the origin and a radius of 1 unit. The point P can move around the circumference of the circle. At point P the \(x\)-coordinate is \(\cos{\theta}\) and the \(y ...

Let's remind ourselves of what the sine graph looks like so that we can see how many solutions we should be expecting: Therefore, from the graph of the function, we can see that we should be ...

With static graphs and equations, it's possible to get a handle on the rules of what various functions do and mean. However, it's still hard to get an intuitive sense of the relationship between ...