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How to factor and expand expressions on a TI-89 Titanium

By E-Code · updated

Press F2 (Algebra) and 2 for factor(, type the expression and ENTER: factor(x^2-5x+6) gives (x-3)·(x-2). F2 3 gives expand(, which multiplies out, so expand((x+1)^3) gives x^3+3·x^2+3·x+1.

Step by step

  1. Open the Algebra menu. F2 Press F2 for the Algebra menu.
  2. Pick factor(. 2 Press 2 for factor(. It splits an expression into the pieces that multiply to make it.
  3. Type the expression. X ^ 2 − 5 X + 6 ) Type x^2-5x+6 and ).
  4. Factor it. ENTER Press ENTER.
  5. Pick expand(. F2 3 Press F2, then 3 for expand(. It does the opposite: it multiplies everything out.
  6. Type the expression. ( X + 1 ) ^ 3 ) Type (x+1)^3 and ).
  7. Expand it. ENTER Press ENTER.
  8. Read both answers. x²-5x+6 = (x-3)(x-2), so x = 3 and x = 2 make it zero. (x+1)³ = x³+3x²+3x+1.

What the screen shows

x²-5x+6 = (x-3)(x-2), so x = 3 and x = 2 make it zero. (x+1)³ = x³+3x²+3x+1.

Look for x^3+3·x^2+3·x+1 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 “Factor and expand expressions” on the TI-89 calculator

Related

Math programs for the TI-89 Titanium:

All TI-89 algebra guides · All TI-89 guides · All calculator guides