How it works The button opens this sheet in the CiNotes notes editor, ready to change. It’s 712 words, so it’s a one-time $3 (typed notes are free up to 300 words). You get a ZIP by email to send to your calculator. Works on the TI-84 Plus CE and CE Python. On OS 5.5 or newer, do the
free one-time setup first.
Algebra 2 formula sheet
The rules and formulas that come up all year in Algebra 2. Delete what your class doesn’t cover and add your teacher’s examples in the editor.
Lines
| Slope | m = (y2 − y1)/(x2 − x1) |
|---|
| Forms | slope-intercept y = mx + b; point-slope y − y1 = m(x − x1); standard Ax + By = C |
|---|
| Parallel and perpendicular | same slope; slopes multiply to −1 |
|---|
| Distance and midpoint | d = √[(x2 − x1)2 + (y2 − y1)2]; M = ((x1 + x2)/2, (y1 + y2)/2) |
|---|
Exponents and radicals
| Product and quotient | xᵃ·xᵇ = xᵃ⁺ᵇ; xᵃ/xᵇ = xᵃ⁻ᵇ |
|---|
| Power | (xᵃ)ᵇ = xᵃᵇ; (xy)ᵃ = xᵃyᵃ |
|---|
| Zero and negative | x0 = 1 (x ≠ 0); x−a = 1/xᵃ |
|---|
| Rational exponent | xm/n = ⁿ√(xᵐ) |
|---|
| Radicals | √(ab) = √a·√b; √(a/b) = √a/√b; rationalize with the root or the conjugate |
|---|
| Radical equations | check for extra solutions after squaring both sides |
|---|
Factoring
| Difference of squares | a2 − b2 = (a + b)(a − b) |
|---|
| Perfect squares | a2 ± 2ab + b2 = (a ± b)2 |
|---|
| Sum of cubes | a3 + b3 = (a + b)(a2 − ab + b2) |
|---|
| Difference of cubes | a3 − b3 = (a − b)(a2 + ab + b2) |
|---|
| ax2 + bx + c | find two numbers that multiply to ac and add to b, then group |
|---|
Quadratics
| Forms | standard y = ax2 + bx + c; vertex y = a(x − h)2 + k; factored y = a(x − r1)(x − r2) |
|---|
| Vertex and axis | x = −b/(2a) |
|---|
| Quadratic formula | x = [−b ± √(b2 − 4ac)]/(2a) |
|---|
| Discriminant | b2 − 4ac: positive, 2 real solutions; zero, 1; negative, 2 complex |
|---|
| Sum and product of roots | −b/a and c/a |
|---|
| Completing the square | add (b/2)2 when a = 1 |
|---|
Complex numbers
| Powers of i | i = √−1; i2 = −1; i3 = −i; i4 = 1, then it repeats |
|---|
| Conjugates | (a + bi)(a − bi) = a2 + b2; divide by multiplying top and bottom by the conjugate |
|---|
Polynomials
| Remainder theorem | p(x) ÷ (x − c) leaves remainder p(c) |
|---|
| Factor theorem | p(c) = 0 means (x − c) is a factor |
|---|
| Rational root theorem | possible roots ± (factors of the constant)/(factors of the leading coefficient) |
|---|
| Fundamental theorem | degree n means n roots, counting multiplicity and complex roots |
|---|
Functions
| Operations | (f + g)(x) = f(x) + g(x); (f ∘ g)(x) = f(g(x)) |
|---|
| Inverses | swap x and y, solve for y; f(f−1(x)) = x; passes the horizontal line test |
|---|
| Transformations | y = f(x − h) + k: right h, up k; y = −f(x) flips over the x-axis; y = a·f(x) stretches by a |
|---|
| Absolute value | |x| = a: x = ±a; |x| < a: −a < x < a; |x| > a: x < −a or x > a |
|---|
Exponentials and logs
| Definition | logb x = y means bʸ = x |
|---|
| Log rules | log(xy) = log x + log y; log(x/y) = log x − log y; log(xᵖ) = p log x |
|---|
| Change of base | logb x = log x / log b |
|---|
| Growth and decay | y = a(1 + r)t; y = a(1 − r)t |
|---|
| Interest | A = P(1 + r/n)nt; A = Pert |
|---|
Rational expressions and systems
| Rational expressions | factor and cancel; exclude values that make a denominator 0; check answers in the original equation |
|---|
| Systems | substitution or elimination; parallel lines: no solution; same line: infinitely many |
|---|
Sequences, counting and probability
| Arithmetic | an = a1 + (n − 1)d; Sn = n(a1 + an)/2 |
|---|
| Geometric | an = a1rn−1; Sn = a1(1 − rⁿ)/(1 − r); infinite S = a1/(1 − r) when |r| < 1 |
|---|
| Permutations | nPr = n!/(n − r)! (order matters) |
|---|
| Combinations | nCr = n!/[r!(n − r)!] (order doesn’t matter) |
|---|
| Probability | P(A or B) = P(A) + P(B) − P(A and B); independent: P(A and B) = P(A)P(B) |
|---|
| Circle | (x − h)2 + (y − k)2 = r2 |
|---|
On the TI-84 Plus CE
| Graphing | Y= to enter, GRAPH to see; 2ND TRACE (CALC) for zero, minimum, maximum, intersect |
|---|
| Fractions | MATH ▸ ▸Frac turns a decimal answer into a fraction |
|---|
| Counting | MATH ▸ PRB: nPr, nCr, ! |
|---|
| Complex answers | MODE ▸ a+bi |
|---|
What it looks like on the calculator
The calculator version is the same sheet in plain text with short lines, so it fits the screen. Square roots are written as sqrt( ), powers with ^ and Greek letters as words. On the calculator, search a word like “vertex” or “discriminant” to jump straight to it. The notes are stored in Archive, so a RAM clear won’t erase them.
Put this on my TI-84 Plus CE
Want your own class notes on there too?
Upload your teacher’s study guide or review packet as a PDF ($3 for up to 10 pages), or paste in your own notes. Diagrams come through as pictures.
Upload my notes or PDFCommon questions
How much does it cost to put this on my calculator?
This sheet is 712 words, so it’s a one-time $3. Typed notes are free up to 300 words and $3 from 301 to 10,000 words. If you cut it down to 300 words or fewer, it’s free. You can also add your own notes to the same order, up to 10,000 words in total (about 9,288 more words).
Can I change the notes before I pay?
Yes. The button opens the sheet in the CiNotes notes editor. Delete what you don’t need, add your teacher’s examples, and check the calculator preview before you check out.
Will it work on my calculator?
It works on the TI-84 Plus CE and the TI-84 Plus CE Python. It doesn’t work on the TI-84 Evo or on black-and-white TI-84s. If your calculator is on OS 5.5 or newer, it needs a free one-time setup first. The setup guide walks you through it.
Will the notes disappear if my calculator resets?
No. The notes are stored in Archive, so a RAM clear won’t erase them. On OS 5.5 or newer, open AsmHook2 from the APPS menu once after a RAM clear, then open your notes as usual.
More subject sheets: AP Chemistry, Chemistry, AP Physics 1, AP Calculus AB, AP Statistics, Precalculus, Unit circle and trig identities. Or see all formula notes, every way to put notes on a TI-84, and what CiNotes is.
CiNotes