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" I do understand trigonometry concepts, but I want to know if there is a quick & easy way to  memorize trig identities?
Thanks for your help ! 
"



Like how there are many definitions in the English language, there are many identities in the trig world.

A simple math identity is 4 = 3 + 1. In trigonometry, a simple identity can be tangent = sine/cosine.  Just like how we can group English words into categories, such as nouns, verbs, and adverbs, we can cluster our trigonometric identities into groups.

How  some words in the English language are more popular, some of our trigonometric identities are more commonly used.
The ones that are the most common have already been categorized into three well-known groups:

1. First we have the basic identities ::  These are your basic definitions of your six trig functions: Trig identities.

2. The second group is called the Pythagorean identities :: These are called Pythagorean because they make use of the Pythagorean theorem, which says that for a right triangle a^2 + b^2 = c^2, where c is the hypotenuse and a and b are the legs: trig identities.

3. The next group is called the angle sum and difference identities :: These tell you how you can break down a trig function that involves the addition or subtraction of two angles.

the mnemonic

Picture

Picture

keentween

  • Ask
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      • :: Interface
      • :: Inheritance
      • :: Intro To Arrays Java
      • :: Arrays Continued
    • :: CS-A or CS-P?
    • :: Control Structures
    • :: Recursion
    • :: While Do While Loops in Java
    • :: Interface in Java
    • :: ArrayLists
    • :: Java Naming Conventions
    • :: Logic Circuits
    • :: Getters and Setters
    • :: Binary & Hexadecimal
  • Summer 2020 Tutoring
    • :: REPRESENT IT!
    • Pre-Algebra Sessions >
      • :: Basic Division
      • :: Complex Division
      • :: Estimation Division
      • :: Division Practice Problems
    • Algebra II >
      • :: Cubic Equations
      • :: Complex Numbers
    • Chemistry >
      • Molarity Basics
    • C++ Sessions >
      • :: Introduction
      • :: Style v Syntax
      • :: Variables & Data Types
      • :: Intialize/Declare Variables
      • :: Types of Operators
      • :: Strings and Input - Output
      • :: How to Construct Arrays
  • AP Bio
    • :: Sketch Notes >
      • :: Part 1
      • :: Part 2
    • :: epigenetics
    • :: Chi-Squared Tests
    • :: Cancer
    • :: Hox Genes
    • :: Hardy-Weinberg Principle
    • :: Rule of Multiplication + Addition for Punnett Squares
    • :: CRISPR
    • :: Amino Acid
    • :: Peptide
    • :: Why study Peptides
    • :: Aquaporins
    • :: Gram Stains
    • :: Graph on Excel for Bio Lab
  • AP Chem
    • Organic Chemistry
    • I. Properties of Matter >
      • Neutralization
    • II. Periodic table >
      • Org of Periodic Table
      • :: Groups
    • III. Chemical bonding >
      • :: Mass to Mass conversion
      • :: Naming Acids
      • :: Cross Drop Charge
      • :: Predicting Products
      • :: Balance Equation Question
      • :: Learn to Balance Equation
      • :: VSEPR Simulation
    • IV. Molar Mass >
      • ::LR ER and excess reatant
      • :: Molecular/Formula Mass
      • :: Empirical Formula & Molar Mass
      • :: Percentages & Empirical Formula
      • :: Empirical formula
    • IV. Solutions and Solubility >
      • :: Types of Solutions with Solubility Curves
      • :: Solubility Curve
    • V. Easy Tricks and Tips >
      • :: Tip to Molecular Shapes
      • Memorizing Bond Angles and Polarity
      • :: Chemistry Formulas
      • :: Trick Polyatomic ions
    • VI. General AP Concepts >
      • :: Potential Energy Diagrams
      • :: Haber-Bosch
      • :: Le Chatelier
      • :: Pressure & Moles
      • ::Rydberg's Constant vs Unit of Energy
      • :: Equilibrium and RICE Tables
      • :: Kinetics
      • Galvanic Cells
    • :: Flash cards
    • :: VSEPR
  • AP Stats
    • Chi-Squared Tests
    • Solving Chi-Sqd Test Using Sheets
    • Applications of Statistics
    • Standardized Scores
    • Distributions Transformations
  • AP Calc
    • DI Method - Tabular Integration
    • Polar Curves: Tangent Line and Slope
    • Riemann Sums: Left and Right Approximations
    • :: Conic Sections Flash cards
    • :: Parent Functions Flash cards
    • Worked Out Problems >
      • :: Worked Out Problems I
      • :: Worked Out Problems II
      • :: Worked Out Problems III
      • :: Worked Out Problems IV
      • :: Worked Out Problems V
      • :: Worked Out Problems VI
      • :: Worked Out Problems VII
      • :: Worked Out Problems VIII
      • :: Worked Out Problems IX
      • :: Worked Out Problems X
      • :: Worked Out Problems XI
      • :: Worked Out Problems XII
      • :: Worked Out Problems XIII
    • Applying Trig Identities
    • L'Hopital's Rule
    • Differences Between Conic Sections
    • Graphing Conic Sections
    • :: Pre-Calc - Trig Identities
    • Tangent & Normal Lines
    • Indefinite integrals: U Sub
    • Calculus Derivatives >
      • Product Rule
      • Quotient Rule
      • Chain Rule
  • Arduino
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    • :: Backward induction
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    • :: Rotational Matrices
    • :: Primary v Secondary Pollutants
    • :: Black Hole
    • :: Covid-19 Hackathon
    • :: Evolution of Immunizations
    • :: Predictions of Diseases
    • :: Book List
    • :: Patterncount
    • :: Binary Classification
    • :: Cybersecurity
    • :: What is CIA Triad
    • :: What is Networking
    • :: Self Similarity
    • :: Trig Identities
    • :: UIL Number S
    • :: Box Offensive Play
    • :: Why Card Trick Works
    • :: Easy Multiplication
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