E-Code

How to reuse an old answer on a TI-89 Titanium

By E-Code · updated

Press CLEAR, then ▲ to move up into the history until the entry or answer you want is highlighted, and press ENTER to paste a copy of it onto the entry line.

Before you start

Work out 2+3 and 10/4 first, so there is something in your history.

2 + 3 ENTER 1 0 ÷ 4 ENTER

Step by step

  1. Clear the entry line. CLEAR Press CLEAR. The history above still shows 2+3 = 5 and 10/4 = 5/2; only the line you type on is emptied.
  2. Go up into the history. ▲ Press ▲. The cursor moves up into the history and highlights the last answer, 5/2. More ▲ presses go further back.
  3. Paste it. ENTER Press ENTER. A copy of the highlighted 5/2 is pasted onto the entry line.
  4. Keep going. × 2 Press × and 2. The pasted answer is ordinary text, so you can add to it.
  5. Work it out. ENTER Press ENTER. 5/2 × 2 = 5.
  6. Anything can come back. ▲ reaches every entry and answer in the history. ENTER pastes the highlighted one, so you never retype a long answer.

What the screen shows

▲ reaches every entry and answer in the history. ENTER pastes the highlighted one, so you never retype a long answer.

Look for 5/2*2 5 on the screen.

Try it with the keys lit up

This guide is one of E-Code's Learn lessons. Open it on E-Code's TI-89 calculator and each key lights up in turn as you press it.

Try “Reuse an old answer” on the TI-89 calculator

Related

Math programs for the TI-89 Titanium:

All TI-89 hidden tricks guides · All TI-89 guides · All calculator guides