Yes, Excel also has a function to convert polar coordinates to rectangular coordinates and vice versa. The function for converting polar coordinates to rectangular coordinates is called "POLARX" and "POLARY". Here's how you can use these functions:

1. Open a new Excel worksheet and enter the polar coordinates in two adjacent cells. For example, let's say your polar coordinates are r=5 and theta=45 degrees. Enter
   Code:

   "5"

   in cell A1 and
   Code:

   "45"

   in cell B1.
2. In the cell where you want to display the rectangular x-coordinate, enter the formula
   Code:

   "=POLARX(A1,B1)"

   . In this example, you would enter the formula in cell C1. Press enter and the rectangular x-coordinate will be displayed.
3. In the cell where you want to display the rectangular y-coordinate, enter the formula
   Code:

   "=POLARY(A1,B1)"

   . In this example, you would enter the formula in cell D1. Press enter and the rectangular y-coordinate will be displayed.

That's it! Excel will automatically calculate the rectangular coordinates based on the polar coordinates you entered. If you need to convert rectangular coordinates to polar coordinates, Excel also has a function for that called "ATAN2". You can use this function to calculate the angle (theta) and the distance (r) from the rectangular coordinates.