How to Graph 10 Common Functions on the TI-84 Plus CE
Graphing is the TI-84’s superpower. Once you know the keystrokes, you can visualize any function in seconds. Here are the 10 most common functions students graph, with the exact steps for each.
The Basic Method (Works for All 10)
- Press Y=
- Type the function next to Y1=
- Press GRAPH
- If the graph looks wrong, press ZOOM then 6 (ZStandard) to reset the window
1. Linear: y = 2x + 3
Type 2X+3 at Y1 (use the X,T,θ,n key for X). ZStandard shows it perfectly.
2. Quadratic: y = x² – 4
Type X^2-4 (use the x² key). Press 2ND then TRACE (CALC), select 2: zero to find the x-intercepts.
3. Cubic: y = x³ – 2x
Type X^3-2X. Use ZOOM 6, then TRACE to follow the curve.
4. Absolute Value: y = |x – 2|
Press MATH, right arrow to NUM, select 1: abs(, then type X-2) and close the parenthesis.
5. Square Root: y = √(x)
Press 2ND then x² (√), type X, close the parenthesis. Note: only the right half graphs — that’s correct.
6. Sine: y = sin(x)
Type SIN(X) (press the SIN key). Important: check your angle mode first — press MODE and make sure Radian or Degree matches your problem.
7. Cosine: y = cos(2x)
Type COS(2X). For a good view of two full waves, set the window: press WINDOW and set Xmin=-2π, Xmax=2π (type 2ND then ^ for π).
8. Exponential: y = 2ˣ
Type 2^X (use the ^ key). The curve grows fast — ZOOM 6 handles it, or set Ymax=20 in WINDOW.
9. Logarithmic: y = ln(x)
Press LN, type X, close the parenthesis. Like square root, only part of the plane shows — that is the function’s actual domain.
10. Rational: y = 1/x
Type 1/X. You’ll see two separate curves with a gap at x=0 — that gap is the vertical asymptote. Never connect them; the function is undefined at zero.
Pro Tips for Better Graphs
- Multiple functions: enter up to 10 in the Y= menu and compare them side by side.
- Trace values: press TRACE, then arrow left/right to read exact coordinates.
- Intersection: to find where two graphs cross, press 2ND then TRACE, select 5: intersect, and follow the prompts.
- Table view: press 2ND then GRAPH (TABLE) to see x/y values numerically.
- Doing statistics? Our LinReg guide shows how to add regression lines to the same graph.
Frequently Asked Questions
Why is my TI-84 graph blank?
The most common causes are a deselected function or a wrong window. See our graph troubleshooting guide.
How do I make the graph bigger or smaller?
Press WINDOW and adjust Xmin, Xmax, Ymin, Ymax manually, or use ZOOM options 2 (Zoom In) and 3 (Zoom Out).
How do I graph two functions at once?
Enter the second function at Y2= in the Y= menu. Both graph together when you press GRAPH.
Why does my trig graph look wrong?
Check MODE — trig functions need the correct angle setting (radians vs degrees) for your problem.
*Try every example above on our free TI-84 calculator online — no download needed. More tutorials in our TI-84 guides hub.*