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How to find the area under a curve on a TI-84 Plus CE, TI-84 Plus or TI-83 Plus

By E-Code · updated

Graph the function, press 2nd CALC (above TRACE) and 7 for ∫f(x)dx, then type the lower limit, ENTER, the upper limit and ENTER. The calculator shades the area and shows its value.

Before you start

Type the function into the Y= editor first: this guide uses Y1 = X² (Y=, X,T,θ,n, x², then 2nd QUIT).

Y= X,T,θ,n X² 2nd MODE

Step by step

  1. Draw the graph. GRAPH Press GRAPH. Y1 = X² is already typed in for you.
  2. Open CALC. 2nd TRACE Press 2nd, then TRACE. CALC (written above TRACE) holds the graph tools.
  3. Pick ∫f(x)dx. 7 Press 7 for ∫f(x)dx, the area under the curve.
  4. Where it starts. 0 Type 0 for the left end of the area.
  5. Confirm the start. ENTER Press ENTER.
  6. Where it ends. 2 Type 2 for the right end.
  7. Get the area. ENTER Press ENTER. The calculator shades the area and works it out.
  8. Read the area. ∫f(x)dx = 2.666…, which is 8/3: the exact area under X² from 0 to 2.

What the screen shows

∫f(x)dx = 2.666…, which is 8/3: the exact area under X² from 0 to 2.

Look for 2.66 on the screen.

TI-84 Plus CE screen: ∫f(x)dx = 2.666…, which is 8/3: the exact area under X² from 0 to 2.

Try it with the keys lit up

This guide is one of E-Code's Learn lessons. Open it on E-Code's TI-84 calculator and each key lights up in turn as you press it.

Try “Find the area under a curve” on the TI-84 calculator

Related

Math programs for the TI-84 Plus CE:

All TI-84 calculus guides · All TI-84 guides · All calculator guides