What is the second order derivative of a function?
- If you differentiate the derivative of a function (ie differentiate the function a second time) you get the second order derivative of the function
- For a function y = f(x), there are two forms of notation for the second derivative (or second order derivative)
- Note the positions of the power of 2's in the second version
- The second order derivative can also be referred to simply as the second derivative
- Similarly, the 'regular' derivative can also be referred to as either the first order derivative or the first derivative
- The second order derivative gives the rate of change of the gradient function (ie of the first derivative) – this will be important for identifying the nature of stationary points
- When finding second derivatives be especially careful with functions that have negative or fractional powers of x (see Worked Example below).
- Mistakes made with fractions or negative signs can build up as you calculate the derivative more than once.