Solution 11739: Displaying Radicals and Imaginary Numbers in the Solutions Using the TI-89 Family, TI-92 Plus and Voyage™ 200.
How do I get radicals and imaginary numbers to appear in my solutions using the TI-89 family, TI-92 Plus and Voyage 200?
Due to the built-in Computer Algebra System or CAS, the TI-89 family, TI-92 Plus and Voyage 200 can display radicals and imaginary numbers in the calculated solution.
To enable this feature, please follow the steps listed below:
1) Press [MODE] and scroll down to "Complex Format". Using the arrow keys, highlight "2:RECTANGULAR" and press [ENTER].
2) Press [F2] and scroll down to "Exact/Approx". Using the arrow keys, highlight "2:EXACT" and press [ENTER]. Press [ENTER] again to return to the HOME screen.
3) Press [2nd] [√] to insert the radical sign followed by an open parenthesis.
4) Press [(-)]   [)] [ENTER]. The calculator should display 2√21*i as the solution.
Please see the TI-89 family, TI-92 family and Voyage 200 guidebooks for additional information.