Everything your TI-84 can do that nobody taught you.

Short, concrete guides to the features your textbook skipped. Read one a week and you'll stop doing arithmetic by hand on problems the calculator can answer in two keystrokes.

• Apps4 min read

  A tour of the free APPS that came with your calculator

  The `apps` key opens a bundled library that most students ignore. Finance, polynomial root-finder, inequality grapher, conic section plotter, and more — all pre-installed.

• Math2 min read

  Composing functions on the home screen with Y-Vars

  Store `f(x)` in Y1 and `g(x)` in Y2, then compute `f(g(3))` with a single line: `Y1(Y2(3))`. Works for any depth of composition.

• Python4 min read

  How Python programs actually run on your TI-84

  The `.py` files this app generates don't run from the calculator's BASIC environment. Here's what happens when you transfer one and hit `prgm`.

• Graphing4 min read

  Intersections, zeros, max/min, and derivatives on a graph

  After `graph`, the `2nd` + `trace` menu opens a CALC panel that finds roots, intersections, local extrema, definite integrals, and numerical derivatives — all directly on whatever you've plotted.

• Math2 min read

  Keep exact fractions with MATH > Frac

  The calculator displays 0.3333333333 by default. One keystroke flips it to `1/3`. Essential for any algebra answer where decimals won't cut it.

• Menus2 min read

  Put the TABLE into ASK mode and stop re-typing x-values

  The default TABLE is a boring +1 stepping list. Switch Indpnt to Ask and it becomes an on-demand function calculator for any function you stored in `Y=`.

• Math3 min read

  Solve any linear system with rref( in under a minute

  Your calculator does full Gauss-Jordan elimination on command. Two menus, one function, and whatever system you throw at it comes back solved.

• Menus3 min read

  Stop re-typing. Use VARS and Ans like a pro.

  Every previously-calculated value, every regression coefficient, and every function is stored somewhere you can pull back. Here's the map.

• Menus3 min read

  The 2nd and alpha shortcuts every student should memorize

  The yellow `2nd` and green `alpha` labels above every key hide a dense shortcut library. Here are the ones worth knowing by muscle memory.

• Stats4 min read

  The 30-second regression pipeline with L1, L2, and Y-Vars

  Stop typing data points one at a time into LinReg. Enter them once into L1/L2, then run any regression over the same dataset with a single keystroke.

• Menus3 min read

  The built-in equation Solver most students miss

  Buried at the bottom of the `MATH` menu is a numeric solver that handles any equation you can type. It solves things calculator-by-hand can't.

• Graphing3 min read

  ZoomFit, ZStandard, and the window tricks for perfect graphs

  Default window ruins 90% of graphs. Here are the six Zoom presets and one manual trick that make curves actually visible.