Ti-84 Plus Graphing Calculator For Dummies, 2nd Edition

Chapter 5

Working with Complex Numbers

In This Chapter

Setting the mode to a + bi

Entering complex numbers

Deciphering strange-looking results

Utilizing the CMPLX menu

Early on in your math journey, you were probably told that you can’t take the square root of a negative number. Then a teacher blew your mind by saying you really can take the square root of a negative number and the result will contain the imaginary number, i. Complex numbers are of the form a + bi, where a is the real part and b is the imaginary part. Fortunately, your calculator knows how to handle complex numbers. In fact, there’s a CMPLX menu of functions on your calculator designed to accomplish just about any task you need to when working with complex numbers.

Setting the Mode

Try evaluating in your calculator. On the Home screen, press `q_1e. There’s a good chance you’ll get an ERROR: NONREAL ANSWERS message, as shown in the first screen in Figure 5-1.

In Real mode, your calculator usually returns an error ...