MMW-CH2

GE MODULE NO. 2: MATHEMATICS IN THE MODERN WORLD

MODULE OVERVIEW

  • Focus on understanding mathematics as a language with its own symbols, logic, and structure.

  • Major areas of understanding include:

    • Basics of mathematics communication (symbols, language, logic).

    • Important features and rules for writing and comprehension of mathematics.

    • Comparison between mathematical expressions and sentences.

    • Standard conventions in mathematical language for consistency and clarity.

    • Introduction to sets, relations, functions, and logic in mathematical arguments.

LEARNING OBJECTIVES

By the end of this module, students should be able to:

  • Discuss mathematical language, symbols, and conventions.

  • Explain mathematics as a language.

  • Correctly perform operations on mathematical expressions.

  • Recognize mathematics as a useful language in understanding the world.

INTRODUCTION TO MATHEMATICAL LANGUAGE

  • What is Language?

    • Defined as a communication system with sounds, words, and grammar (Cambridge English Dictionary).

    • Mathematics is also considered a language due to its system of symbols and rules.

  • Example:

    • Verbal: "Two added to four is six."

    • Mathematical: 2 + 4 = 6

    • Both forms convey the same idea, illustrating mathematics as a universal language.

CHARACTERISTICS OF MATHEMATICAL LANGUAGE

  • Mathematics enables precise, concise, and powerful expression of thoughts.

  • Classifications in mathematical language:

    • Nouns (Expressions): Represent mathematical objects (e.g., numbers, variables).

    • Examples:

      • English: person, place, thing

      • Mathematical: 5, 3x - 5, ax + by

    • Sentences: State complete thoughts (statements, questions, commands).

    • Examples:

      • English: "Pedro is handsome."

      • Mathematical: 2 + 7 = 9

Nouns vs. Sentences in Mathematical Language

  • Expressions (Nouns) do not express complete thoughts.

  • Mathematical Sentences (Sentences) can be judged as true or false.

  • Verbs in Mathematics: The equal sign = functions as a verb, signifying equality. Connectives such as + link expressions to form compound objects.

LEARNING ACTIVITIES

Learning Activity 1: Identifying Expressions vs. Sentences

  • Identify various items as either mathematical expressions or sentences.

Conventions in Mathematical Languages

  • Mathematics has conventions helping identify expressions and sentences:

    • Expression: Does not convey complete thoughts.

    • Ex: 3x + 7

    • Mathematical Sentence: Expresses a complete thought;

    • Ex: 2 + 7 = 9 states a complete thought and can be evaluated as true.

SYMBOLS AND NOTATION IN MATHEMATICS

Sets and Basic Operations

  • Mathematical symbols for sets and operations:

    • igcup - Union of sets.

    • igcap - Intersection of sets.


    • i - Member of a set.


    • otin - Not a member of a set.

    • extbf{A} = ext{set label,} ext{ e.g. } A = ext{collection of elements}

Basic Operations and Relational Symbols

  • Addition (+), Subtraction (-), Multiplication (*), Division (/): Define operations between numbers.

  • Comparison Symbols:

    • = - Equal to


    • eq - Not equal to

    • > - Greater than

    • < - Less than

    • egin{align} ext{and} \ ext{or} ext{ (logical operations)} ext{ in logical statements.} \ ext{For Ex: } A ext{ and B if A is true and B is true.} \ ext{Equivalents like } A = B ext{ if and only if both are true.} ext{ etc….} ext{ } \ ext{Utilize for defining relationships.}
      ightarrow ext{Express complex relationships clearly through symbols.} ext{ } \ ext{Use Venn Diagrams to illustrate set relations.} \ ext{Illustration of Venn Diagrams showing intersections and unions.} \ ext{Any intersection is common; a union two combined.} ext{ } \ ext{Implications like A implies B, elucidating cause and effect. } \ ext{Logical connectives serve to connect propositions expressively.} ext{Logical connectives guide order of operations in expressions.} ext{ } ext{The combination of expressions yield outputs of logical truth tables.} ext{ } ext{} ext{ } ext{ } ext{} ext{}\ ext{Logic bridges gaps between math, language, and thought processes.}\ ext{Upon benefiting from this bridge, recognizing relations between concepts is essential.} end{align}

  • Quantifying Statements:

    • orall: For all

    • hereexists: There exists

Translation Between English Statements and Symbols

  • Translating verbal language into mathematical notation simplifies problem-solving:

    • Example Translating:

    • English: "The sum of six and two over four is two."

    • Mathematical: \frac{6 + 2}{4} = 2

Set Properties and Classification

  • Set Types:

    • Finite: Countable elements.

    • Infinite: Non-countable elements.

    • Null Set: Set without members, written as ∅.

    • Unit Set: A set with exactly one element.

  • Set Relations:

    • Equivalent: Same number of elements.

    • Equal: Same elements.

Venn Diagrams

  • Used to visualize set operations (union, intersection, etc.).

  • Demonstrate relationships between sets.

  • Example Applications:

    • Assess shared interests among diverse groups.

Cartesian Product

  • Defined as all possible ordered pairs from two sets, $A imes B$.

  • Example Application: Given sets $A = {1, 2}$ and $B = {3, 4}$, produces pairs: $1, 3; 1, 4; 2, 3; 2, 4$.

  • The properties of these sets can be visually represented through set diagrams, refining perspectives of set relationships.


B. THE LANGUAGE OF RELATIONS AND FUNCTIONS

  • Involvement of ordered pairs shows relationships between two sets.

    • A function defines a relation without ambiguity or duplicity in outputs: every input relates to a single output.

    • Example: Function f: X
      ightarrow Y means for each $x ext {in } X$, the function provides one $y ext {in } Y$.

  • Relation Properties:

    • Reflexive: All elements relate to themselves.

    • Symmetric: Relation remains consistent if reversed.

    • Transitive: Establishes continuity through relationships.

    • Antisymmetric: Equality holds with respect to the property.

Function Operations

  • Basic operations on functions include:

    • Sum, Difference, Product, Quotient

    • Composition of Functions

  • Example with functions for clarity:

    • f(x) + g(x) or f(g(x))


C. LOGIC AND FORMALITY IN MATHEMATICS

  • Logic serves as the backbone for reasoning in mathematics.

    • Propositions can either be true or false.

    • Examples include:

    • True: "2 is even."

    • False: "The integer 3 is even."

  • Truth Tables:

    • Construct tables to explore logical connectors: conjunctions, disjunctions, implications, and equivalences.


ASSESSMENT OPPORTUNITIES

  • Engage in practical activities translating verbal statements into mathematical symbols and vice versa to solidify understanding.

  • Activities also include writing and evaluating propositions, completing truth tables for varying conditions and operations in mathematical contexts.


REVISION AND REFLECTION

  • Regularly reassess learned concepts in math and logic, deepen connections between various domains of study and application.

  • Engage insights derived from formal mathematical concepts in practical scenarios.