Go Graphic

# Online Tutorial -CG50: How to Use the Derivative Function

## Video Transcript

In this tutorial, we will be looking at evaluating and graphing the gradient of a curve at a point or a set of points. A calculator which will find an algebraic expression for derive radix isn't allowed in A-level exams. To work along with this tutorial. You may find it easiest to reset the calculator before starting so that your screen matches the one in the video.

In run mode, choose the math menu and d by dx. Type the function using the X Theta T Key and scroll to the right to enter the x value for which the gradient is required. Repeat for the second derivative. You can also graph the gradient of a curve at each point as a gradient function. From the main menu, go to graph mode. Type the function into Y1 and execute. Use the option key and calc to find the derivative. Use Y1 to save typing the function again, scroll right and type x equals X. Using the X Theta T key. This allows the gradient function to be drawn for all values of X. Execute and draw.

The graph suggests that the gradient function, is a simple transformation of the original function, and therefore the gradient might be Y equals 0.3 e to the 0.3x. To check this, you can add that function to your list. Exit Graph and type Y equals 0.3 e to the 0.3x into Y3. Execute and notice the graphs come inside, so there's now plenty of evidence that your answer is correct. You could use this as a checking strategy for all your differentiation questions.

You can find additional resources at education.casio.co.uk