Notation & membership
Roster form lists elements; set-builder form describes them: {x : property}.
Ultra edition · worked examples everywhere · appendices
Twenty chapters with at least two worked examples each, pitfall lists, a deep-dive calculus core — then a symbol glossary, a master cram sheet, and the exam playbook.
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Collections of objects and the algebra of combining them — the language every later chapter is written in.
Roster form lists elements; set-builder form describes them: {x : property}.
Union = either; intersection = both. A ∩ B = ∅ means disjoint.
Complement is relative to the universal set U.
Prove A = B by showing A ⊆ B and B ⊆ A.
Three equivalent statements.
Add sizes, subtract the overlap counted twice.
Subtract pairwise overlaps, add back the triple.
Complement flips ∪ ↔ ∩.
Intersection distributes over union — and vice-versa.
∅ is neutral for ∪; U for ∩.
n elements → 2ⁿ subsets, counting ∅ and A itself.
Ordered pairs; in general A × B ≠ B × A. Functions are built from these.
Class of 40: 25 like algebra, 20 geometry, 8 both. How many like neither?
Answer
List all subsets of {a, b}.
Answer
Statements, implications and quantifiers — the grammar of proof.
False only when p true, q false.
Logically identical — often the easiest proof route.
“iff” = two proofs.
Push NOT through: AND ↔ OR flips.
Swap ∀ ↔ ∃, negate inside.
Affirm the hypothesis; deny the conclusion.
Implications chain; an “or” plus one denial settles the other.
True in every truth-table row, or in none.
Negate: “Every prime greater than 2 is odd.”
Answer“There exists a prime > 2 that is not odd.”
Write the contrapositive of “if x² is even, then x is even.”
Answer“If x is odd, then x² is odd.” (This is how the theorem is actually proved.)
ℕ ⊂ ℤ ⊂ ℚ ⊂ ℝ ⊂ ℂ — and the distance function that makes inequalities behave.
Rationals are ratios p/q; √2, π are irrational.
Distance from zero — always ≥ 0.
“less thAND”, “greater thOR”.
|x − a| = distance from x to a.
A shortcut never beats both sides added.
Multiply by negative → reverse the sign.
Fractional = root + power; negative = reciprocal.
The last one needs the absolute value.
Round = excluded; square = included.
Solve
Answer
Simplify
Answer
Adjoining √(−1) — every polynomial gets roots, and rotation becomes multiplication.
Powers cycle: 1, i, −1, −i.
Point (a, b) in the Argand plane.
Conjugate reflects across the real axis.
FOIL, then i² → −1.
Multiply top and bottom by the conjugate of the denominator.
Modulus respects products.
r = |z|, tan θ = b/a (fix quadrant). Multiplying = scale + rotate.
The exponential unifies trigonometry.
Modulus to the n, argument times n.
A regular n-gon on a circle of radius ⁿ√r.
Δ < 0 → conjugate pair.
Compute
Answer
Simplify
Answer
One output per input — composing, inverting, sliding and stretching graphs.
Inside-out. In general f ∘ g ≠ g ∘ f.
Graphs mirror across y = x; only one-to-one functions invert.
h right, k up, |a| vertical stretch, b compresses horizontally by 1/b.
cos, x² even; sin, tan, x³ odd.
Secant slope — the warm-up for the derivative.
Let h → 0 and this becomes f′(x).
| f(x) | ||||||
|---|---|---|---|---|---|---|
| domain | ||||||
| range |
Every graph this semester is a transformation of these six parents.
Vertical test → function? Horizontal test → invertible?
One y per x; one x per y.
Verify with f(f⁻¹(x)) = x.
: find (g ∘ f)(x) and its domain.
Answer, domain
Find the inverse of
Answer
Where polynomials cross the axis, and what the coefficients whisper about those crossings.
Works every time.
Reads the roots before you solve.
Cubic: α+β+γ = −b/a, αβγ = −d/a.
Division by (x − a) leaves remainder f(a).
Axis of symmetry x = h.
Factors of the constant over factors of the leading coefficient.
Difference of squares; sum/difference of cubes.
Sketch: a > 0 smiles, a < 0 frowns.
Degree n ⟹ exactly n complex roots, counting multiplicity.
Why complex numbers exist.
Solve
Answer
For what k does have a double root?
Answer (root x = −2)
Inverse operations: exponents grow, logarithms ask “to what power?”
A logarithm is an exponent in disguise. Domain x > 0.
Multiplication becomes addition.
Any base via ln or log₁₀.
Inverses undo each other — the key solving move.
The base that grows at its own rate.
Discrete vs continuous compounding.
Set A = 2P or P/2 and solve.
Isolate the exponential, then log both sides.
Solve
Answer
Solve
Answer
Patterns indexed by n — adding them up, sometimes forever.
Constant step d.
Gauss: pair first with last.
Constant ratio r.
r = 1 gives Sₙ = n·a₁.
Converges only for |r| < 1.
Σc = nc; constants factor out.
Always G.M. ≤ A.M.
Every repeating decimal is a GP.
a₃ = 7, a₈ = 22. Find S₁₀.
Answer
Sum
Answer
Expanding (a + b)ⁿ without multiplying n times.
Exponents in each term add to n.
Grab any single term without expanding.
Symmetry and the triangle rule.
Set a = b = 1 for the 2ⁿ sum.
Set a = 1, b = −1: the two halves are equal, each 2ⁿ⁻¹.
Parity of n decides.
For “the term in x²”: write the general term, match powers, solve for k.
Never expand the whole thing.
Coefficient of x² in
Answer
Find the middle term of
Answer — it's also the term independent of x.
Counting arrangements — the whole chapter turns on: does order matter?
Ways to order n distinct objects.
Count slot by slot, multiply.
Order matters: podiums, passwords.
Order doesn't: committees, card hands.
Each group hides r! orderings.
Divide by each run of identical items.
Pin one person, arrange the rest.
Glue for “together”; complement for “apart”.
The universal shortcut for “at least” questions.
Arrangements of BANANA?
Answer
Choose a 3-person committee from 8 people.
Answer
Angles, the unit circle, and the six functions that turn geometry into algebra.
Right-triangle definitions.
Extends trig to every angle.
Arc length and sector area need radians.
csc↔sin, sec↔cos, cot↔tan.
For y = sin(bx) the period becomes 2π/b; tan gives π/b.
Amplitude |a|, period 2π/b, shift c, midline d.
Reduce to Q1, fix the sign with ASTC.
Principal values only.
All · Sin · Tan · Cos
Positive functions in quadrants I–IV.
| θ | 0° | 30° | 45° | 60° | 90° |
|---|---|---|---|---|---|
| sin θ | |||||
| cos θ | |||||
| tan θ | undef. |
Memorize it — it powers half of Ch 12 and the calculus trig work.
Solve on
Answer
Find cos 120° exactly.
Answer
Rewriting trig into the form the problem demands — and solving non-right triangles.
One identity, three disguises.
sin, tan odd; cos even.
Cosine flips the sign.
Pick the form that cancels.
Squared trig → linear in cos 2θ. Essential for Ch 19.
Products become integrable sums.
Great for factoring equations.
One sinusoid; extrema ±R.
Sine rule: opposite pairs. Cosine rule: SAS or SSS.
Two sides + included angle.
Write as R sin(θ + α); state the max.
Answer, max 5
Solve on
Answer
Magnitude and direction — plus two very different ways to multiply.
Pythagoras in 2D/3D.
Componentwise; normalize to length 1.
Result is a scalar.
Dot > 0 acute, = 0 right, < 0 obtuse.
One is a vector, one is a length.
In 2D: |u₁v₂ − u₂v₁|. Half of it is the triangle area.
Only the along-motion component counts.
: dot product and angle.
Answer
Area of the triangle spanned by
Answer
Arrays encoding linear systems — with one surprise: multiplication doesn't commute.
Row of A · column of B; inner dims match.
In general AB ≠ BA, and AB = 0 doesn't force A = 0 or B = 0.
Never divide by a matrix.
Main diagonal minus anti-diagonal.
Swap diagonal, flip the rest, divide by det.
Also — order reverses.
Transpose also reverses order.
Determinant behavior under elimination.
Replace column with constants, det, divide.
det = 0 → none or infinitely many solutions.
Solve
Answer
: compute AB and BA.
AnswerAB ≠ BA — order matters, concretely.
Equations as pictures: slopes, distances, and the curves from slicing a cone.
Vertical: undefined; horizontal: 0.
Point-slope, slope-intercept, general.
Negative reciprocals.
Pythagoras; averaging coordinates.
Shortest distance from (x₀, y₀) to Ax + By + C = 0 — the tangency test for circles.
Center (h, k); signs flip when reading off.
+ → ellipse, − → hyperbola, one square → parabola.
Conics are focus–directrix distance ratios (eccentricity).
The standard move for finding circle centers.
Center & radius of
Answercenter (3, −2), r = 5
Bisector of the segment from (1, 2) to (5, 6)?
Answer
The doorway to calculus: what a function approaches — even where it isn't defined.
Limits pass through +, −, ×, ÷.
Radians; for small x, sin x ≈ x.
Multiply by (1 + cos x) first.
eˣ ≈ 1 + x and ln(1 + x) ≈ x, made rigorous.
Compound interest pushed to continuous.
Within ε of L by staying within δ of a.
Fail any one and the graph breaks.
Classify before describing.
Both sides must agree; blow-up → vertical asymptote.
Degree showdown → horizontal asymptote.
Check both sides of every vertical candidate.
Standard for oscillating factors like sin(1/x).
0/0 means factor and cancel.
Answer (removable hole)
Answer
Find k so is continuous at 1.
Answer
One limit definition, a complete toolbox of rules, and four techniques for every shape of function.
Tangent slope as the secant tightens.
Any real n — negatives and fractions included.
Term by term; constants die.
E.g. .
low·D-high − high·D-low, over low².
Outside-in; multiply by the inner derivative.
Co-functions carry a minus.
e^x equals its own derivative.
arccos is the negative twin.
Each y-term picks up a dy/dx; collect and solve.
The weapon for xˣ and product towers.
Reciprocal slope at the mirrored point.
Powers substitution in Ch 19.
| f(x) | f′(x) | f(x) | f′(x) |
|---|---|---|---|
Everything else is this table plus product, quotient and chain.
Differentiate
Answer
Differentiate
Answer
Slope of at (1, 2).
Answer
Tangents, motion, extrema, concavity — plus related rates and optimization.
Normal line: slope −1/f′(a).
Speeding up ⟺ v, a same sign.
Sign of f′ = direction of the graph.
Extrema can only occur here.
Sign chart of f′ — always reliable.
f″(c) = 0 → test silent; use the sign chart.
Inflection = f″ changes sign.
Global extrema live among these values.
Rolle: f(a) = f(b) ⟹ f′(c) = 0.
Confirm the form first; repeatable.
Tangent as estimator; differential as error propagator.
Every time-varying variable earns a d/dt term.
Run in order — each step narrows the picture.
100 m fencing, three sides (barn is the fourth). Maximize area.
Answer
Ripple expands at dr/dt = 2 m/s. dA/dt when r = 5?
Answer
Answer
Estimate by hand.
Answer
Differentiation run backwards — and, via the Fundamental Theorem, exact areas.
Area as the limit of finer rectangles.
n = −1 is the log case.
Ch 17's table read right-to-left.
sin²/cos²: power-reduce first.
| Integral | Antiderivative | Integral | Antiderivative |
|---|---|---|---|
Linear inside? Divide by its slope a. The pattern behind u-substitution.
Split sums, pull out constants.
Definite integral = antiderivative at the ends.
Upper limit g(x) → chain: f(g(x))·g′(x). Exam favorite.
Splitting and reversing intervals.
Chain rule in reverse.
Change bounds with the variable — no back-substitution.
Top minus bottom; intersections give the bounds.
Some c satisfies f(c) = f_avg (MVT for integrals).
Scan for the derivative of the inside — the #1 tell.
Answer
Answer
Area enclosed by and .
Answer
Differentiate
Answer
Quantifying chance and summarizing data — where Ch 1's sets get measured.
Equally likely outcomes assumed.
“At least one” = 1 − P(none).
Mutually exclusive → just add.
Sample space shrinks to B.
No influence ⇔ multiply.
Bayes' denominator machinery.
Update belief with evidence; P(A|B) ≠ P(B|A).
k successes in n independent trials.
Expected successes = n·p.
σ in the data's units; σ² is not.
Long-run average; σ's from the mean.
Two fair dice: P(sum = 7)?
Answer
5 fair coin flips: P(exactly 3 heads)?
Answer
Every mark you've met this semester, in one table — read it aloud column by column and the course sounds like a sentence.
| Symbol | Name | How to read it |
|---|---|---|
| element of | x ∈ A — “x belongs to A” | |
| not element of | y ∉ A — “y is not in A” | |
| subset | A ⊆ B — every element of A is in B | |
| union | in A or B (or both) | |
| intersection | in both A and B | |
| empty set | the set with no elements | |
| power set | the set of all subsets of A | |
| Cartesian product | A × B — all ordered pairs (a, b) | |
| for all | ∀x — “for every x” | |
| there exists | ∃x — “at least one x” | |
| negation | ¬p — “not p” | |
| conjunction | p ∧ q — “p and q” | |
| disjunction | p ∨ q — “p or q (or both)” | |
| implies | p ⇒ q — “if p then q” | |
| iff | p ⇔ q — “p if and only if q” | |
| absolute value / modulus / size | distance from 0; |z|; |A| = number of elements; a | b = divides | |
| square root | the non-negative number whose square is x | |
| infinity | unbounded growth — not a number | |
| constants | π ≈ 3.14159; e ≈ 2.71828 | |
| number sets | naturals · integers · rationals · reals · complex | |
| summation | Σ aₖ — add the terms as k runs its range | |
| integral | ∫ f dx — signed area / antiderivative | |
| limit | the value f approaches as x approaches a | |
| derivative | instantaneous rate of change of f | |
| approximately | ≈ — close to, not exactly | |
| perpendicular | meeting at 90°; u ⊥ v ⟺ u·v = 0 | |
| change / discriminant | Δy = change in y; Δ = b² − 4ac | |
| mean, std deviation | center and spread of data | |
| probability | chance of A; chance of A given B |
If a symbol on an exam question stops you cold, find it here first — notation is half the subject.
The twenty-four formulas most likely to appear, anywhere, in any form. If you know these cold, you can rebuild the rest.
The non-mathematical skills that decide 10–15% of the grade: how to run the paper, and how to check the answers.