The a+bi Command Command Summary

Puts the calculator into a+bi mode.

Command Syntax

a+bi

Press:

1. MODE to access the mode menu.
2. Use the arrow keys and ENTER to select a+bi

TI-83/84/+/SE

1 byte

The a+bi command puts the calculator into rectangular complex number mode. This means that:

• Taking square roots of negative numbers, and similar operations, no longer returns an error.
• Complex results are displayed in the form a+bi (hence the name of the command)

This is the standard way of displaying complex numbers, though they can also be displayed in polar form (see re^θi for more details). To extract the coefficients a and b, use the real( and imag( commands.

Rather than switch to a+bi mode, you might want to force the calculations to use complex numbers by making the original argument complex. The general way to do this is by adding +0i to the number. However, there may be an optimization in any particular case. See the quadratic formula routine for a good example of this.

``````Real
Done
√(-1)
(causes an error)
√(-1+0i)
i```
```