Trigonometric graphs can be sketched when you know the amplitude, period, phase and maximum and minimum turning points. Learn about graphs of trigonometric functions in this National 5 Maths guide.

If \(f(x) = x^2\), then \(-f(x) = -(x^2)\). This means that each of the \(y\) coordinates will have a sign change. So \(y = 4\) would become \(y = -4\), and \(y = -1 ...