Dr. J's Maths.com
Where the techniques of Maths
are explained in simple terms.

Welcome to the Wonderful World of Maths.
Test Yourself.

• Algebra & Number
  • Main Algebra page
  • Equations
    • Blood alcohol (BAC)
  • Factorisation
  • Indices
  • Fractions - algebraic
  • Absolute values
  • Inequalities
  • Irrationals
• Calculus
  • Differentiation
    • Main page
    • Max-min questions
    • Implicit differentiation
  • Integration
    • Main page
    • Approximation methods
    • Areas
    • Volumes
    • Reverse Chain Rule
  • Applics to physical world
  • Historical development
• Financial Maths
  • Main Finance page
  • Earning money & Tax
  • Standard Investments & Loans
  • Series
  • Series - Annuities & Loans
• Functions & Quadratics
  • Main page
  • Characteristics
  • Transformations
  • Linear fns
  • Quadratics
  • Exponential
    • Main page
  • Hyperbola
  • Logarithmic
    • Main page
  • Trigonometric
    • Main page
  • Parametric
  • Inverse functions
    • Inverse fns
    • Inverse trig fns.
• Geometry
  • Parallel lines
  • Triangles
    • Types
    • Congruence
    • Similarity
  • Pythagoras' Theorem
  • Quadrilaterals
  • Circles
    • Arc length, sectors etc
• Measurement
  • Errors of measurement
  • Perimeter & area
  • Surface area & volume
  • Energy and mass
    • Units
    • Food & exercise
    • Electricity
  • Time
    • UTC, GMT & IDL
• Networks & Graphs
• Probability & Statistics
  • Probability main page
  • Data presentation
  • Descriptive statistics
    • Main page
    • Calculator use
  • Probability distributions
  • Normal distribution
  • Binomial distribution
• Trigonometry
  • Measuring angles
    • Main page
  • Equations & identities
  • Graphing trig functions
  • Calculus and trig functions
  • Inverse trig fns
• Maths & beyond
  • Bibliography
  • Maths humour
• Index

 

Davids idea that point your 12 on an analogue watch to the sun. the point half way between the 12 and the time is pointing to the north in the southern hemisphere.