Math 113 _ Chapters 1 & 2
Fibonacci sequence
1,1,2,3,5,8,13,21,34,55,89,144,... NOT Arithmetic because there is no fixed difference. First two terms of the Fibonacci sequences and 1, 1 and each subsequent is the sum of the previous two.
Well-defined set
Must be able to identify whether or not an object is an element of that set
Statement
a sentence that is either true or false, but not both
Recursive pattern
after one or more consecutive terms are given, each successive term of the sequence is obtained from the previous term(s)
Biconditional
"p if, and only if, q"
Equal Sets
two sets are equal if, and only if, they contain exactly the same elements
Law of Denying the Consequent (modus Tollens)
With a conditional accepted as true but having a false conclusion, the hypothesis must be false.
Universal Quantifiers
Words: all, every, & no Refer to each and every element
Figurative Number
examples of sequences that are neither arithmetic nor geometric
Conjectures
statements or conclusions that have not been proven
Set Intersection
the intersection of two sets A and B, is all elements common to both A and B
Inductive reasoning
the method of making generalizations based on observations and patterns
Guess and Check
First guess at an answer using as reasonable a guess as possible. Then we check to see whether the guess is correct. If not, the next step is to learn as much as possible about the answer based on the guess before making a next guess.
Cartesian Product
For any sets A and B, the Cartesian product of A and B, written AxB, is the set of all ordered pairs such that the first component of each pair is an element of A and the second component of each pair is an element of B
Fundamental Counting Principle
If event M can occur in m ways and, after it has occurred, event N can occur in n ways, then event M followed by event N can occur in mn ways
One-to-one Correspondence
If the elements of sets p and s can be paired so that for each element of p there is exactly one element of s and for each element of s there is exactly one element of p, then the two sets p and s
Law of Detachment (Modus Ponens)
If the statement "if p, then q" is true and p is true, then q must be true
Equivalent Sets
Two sets A and B are equivalent, written A~B if and only if there exists a one-to one correspondence between the sets -have the same number of elements and are not necessarily equal but they could be
Set Union
Union of two sets A and B, Written A U B, is the set of all elements in A or in B
Existential Quantifiers
Words: some & there exists at least one Refer to one or more, or possibly all, of the elements
Counterexample
an example that shows a conjecture is false
Problem Solving
finding a way out of difficulty, a way around an obstacle, attaining an aim which was not immediately attainable
Logically Equivalent
if, and only if, two statements have the same truth values in every possible situation
Cardinal Number
n(s) number of elements in set
Deductive reasoning
the use of definitions, undefined terms, mathematical axioms that are assumed to be true, and previously proved theorems, together with logic to prove these conjectures
4-Step problem solving process
1. Understanding the problem 2. Devising a plan 3. Carrying out the plan 4. Looking back
Truth Tables
Show all possible true-false patterns for statements
Chain rule (Transitivity)
If "if p, then q" and "if q, then r" are true, then "if p, then r" is true
Quantifiers
Are more complicated to negate Words: all, some, every, & there exists
Geometric sequence
2,4,8,16,32 Each successive term of a geometric sequence is obtained from its predecessor by multiplying by a fixed nonzero number, the ratio.
Subset
B is a subset of A, if and only if, every element of B is an element of A
Relative Complement
Complement of A relative to B, written B - A, is the set of all elements in B that are not in A
Arithmetic sequence
Sequence in which each successive term from the second term on is obtained from the previous term by the addition (+) or subtraction (-) of a fixed number
Conditionals or Implications
Statements expressed in the form "if p, the q" denoted by p -> q. Can also be read "p implies q"
Set Complement
The complement of set F, written F with a line on top, is the set of all elements in the universal set U that are not in F