# The Math CPX Submenu on the TI-83 Plus

The Math CPX submenu on the TI-83 Plus graphing calculator contains the standard functions used with complex numbers. You can insert a Math menu function into an expression.

## Find the conjugate of a complex number

The **conj** function evaluates the conjugate of the complex number or arithmetic expression that follows the function. This number or expression must be enclosed in parentheses. The calculator supplies the opening parenthesis; you must supply the closing parenthesis.

## Find the real or imaginary part of a complex number

The **real** and **imag** functions find (respectively) the real and imaginary parts of any complex number or arithmetic expression that follows the function. This number or expression must be enclosed in parentheses. The calculator supplies the opening parenthesis; you must supply the closing parenthesis.

## Find the polar angle and modulus (magnitude) of a complex number

The **angle** and **abs** functions respectively find the polar angle and the magnitude (modulus) of the complex number or arithmetic expression that follows the function. This number or expression must be enclosed in parentheses. The calculator supplies the opening parenthesis; you must supply the closing parenthesis.

The **angle** function gives the polar angle in radians if the calculator is in Radian mode, or in degrees if the calculator is in Degree mode.

## Converting between rectangular and polar form

The **Rect **function** **converts a complex number from polar form to rectangular from. The polar form of the complex number must come before the **Rect **function.

The **Polar **function** **converts a complex number from rectangular form to polar from. The rectangular form of the complex number must come before the **Polar **function. This function won’t convert a real number to polar form; instead, it returns the ERR: DATA TYPE error message.

If the answer produced by employing either of these functions doesn’t fit on the screen, repeatedly press

to display the rest of the answer.