Exam 1: Sets and Combinations Ch 1: sets 1.1: set operations: intersection, union, complement, cartesian product. 1.2: Venn diagrams + counting * partitions (disjoint unions): n(A "+" B) = n(A) + n(B), where "+" means disjoint union. * cartesian products: n(A x B) = n(A)*n(B) + deMorgan's laws: * (A union B)' = A' intersect B' * (A intersect B)' = A' union B' 1.3: counting * n(A union B) = n(A) + n(B) - n(A intersect B). 1.4: trees: counting possible outcomes of a sequence of experiments by multiplying number of possible outcomes of a sequence of experiments. Ch 2: Combinatorics (counting) 2.1: Probabilities * sum of probabilities of all outcomes is 1. * Pr(E) = n(E)/n(sample space) if all outcomes are equally likely 2.2: Permutations (order matters) P(n,r) = n!/(n-r)! = n*(n-1)*...*(n-r+1) = permutations of n objects taken r at a time 2.3: Combinations (order doesn't matter) C(n,r) = P(n,r)/r! = combinations of n objects taken r at a time Exam 2: Probability Ch 3: Probability of events 3.1: axioms and properties of probability * probability measures the size of a set of outcomes. * axioms: 1. 0 <= Pr[E] <= 1 2. Pr[S] = 1 3. Pr[E "+" F] = Pr[E] + Pr[F]. * properties: 1. Pr[E'] = 1 - Pr[E] 2. Pr[E union F] = Pr[E] + Pr[F] - Pr[E intersect F] 3.2: conditional probability * Pr[A|B] := Pr[A and B]/Pr[B] * A and B are independent if Pr[A and B] = Pr[A]*Pr[B], i.e., knowledge of one event gives no information about the probability of the other. 3.3: trees (to depict outcomes of stochastic processes) 3.4: Bayes probabilities * the probability of a leaf of a tree is the product of the conditional probabilities along the branches to that leaf; * Bayes' formula expresses this idea: Pr[A|B] = Pr[B|A]Pr[A]/Pr[B] (for two events). * Bernoulli process: for n independent Bernoulli trials each with probability of success p and probability of failure q = 1-p, Pr[r successes] = C(n,r) p^r q^(n-r) Ch 4: Random Variables (random numbers) 4.1: probability density function * binomial random variable = number of successes of Bernoulli process 4.2: Expected value * definition Let X = random variable with k outcomes. Let x_j = outcome number j. Let p_j = P(X=x_j). Then E[X] = x_1*p_1 + x_2*p_2 + ... + x_k*p_k. * expectation of binomial random variable: E[X] = n*p, (n trials each with success probability p) * variation and standard deviation: Let m = E[X]. Var[X] = (x_1 - m)^2*p_1 + (x_2 - m)^2*p_2 +...+ (x_n - m)^2*p_n. standard deviation = sigma = sqrt(Var[X]). * variance of binomial random variable: Var[X] = n*p*q. Exam 3: Linear Algebra Ch 5: systems of equations 5.1: lines * slope = m = rise over run = (y_2 - y_1)/(x_2 - x_1) * use point-slope formula and/or slope-intercept formula to find the equation of a line through two points 5.2: linear systems * substitution method * reduction method (combining equations) 5.3 linear systems in many variables (*important*) * 3D graphs of planes * matrix representation * row operations * row reduction * reduced form * solution sets + unique solution + overdetermined case (inconsistent system) + underdetermined case (infinite family of solutions) Ch 6: Matrix algebra - matrix addition and multiplication - matrix identity - matrix inverse - using matrix inverse to solve linear systems Exam 4: Applications Ch 7: Linear programming - feasible sets - evaluation at corner points and auxiliary points Ch 8: Markov Chains - state transition matrix - state vectors - regular markov chains - stable state vector Final material Ch 9: financial math - compound interest - present and (future) amount - present value of annuity - amount of annuity - payment of ammortized loan - payment of sinking fund