Small Angle Approximations Small angle approximations When an angle measured in radians is very small, you can approximate the value using small angle approximations These only apply when angles ar...
Trigonometry Exact Values Exact values In trigonometry some values of sin, cos and tan are “nice” For example sin 30° = ½, tan 45° = 1 We can find those associated with the angles 30°, 45° and 60° ...
Radian Measure Radian measure Radians are an alternative to degrees for measuring angles 1 radian is the angle in a sector of radius 1 and arc length 1 Radians are normally quoted in terms of π Thi...
Edexcel IGCSE Physics: Double Science 复习笔记： 3.1.7 Dangers of EM Waves Dangers of EM Waves As the frequency of electromagnetic (EM) waves increases, so does the energy Beyond the visible...
Edexcel IGCSE Physics: Double Science 复习笔记：3.1.6 Applications of EM Waves Applications of EM Waves Electromagnetic waves have a variety of uses and applications The main ones are summar...
Strategy for Trigonometric Equations How to approach solving trig equations You can solve trig equations in a variety of different ways Sketching a graph (see Graphs of Trigonometric Functions) Usi...
Quadratic Trigonometric Equations Solving quadratic trigonometric equations If an equation involves sin2θ or cos2θ then it is a quadratic trigonometric equation These can be solved by factorising a...
Linear Trigonometric Equations Solving linear trigonometric equations You should have already seen two ways to solve linear trig equations By sketching the graph (see Graphs of Trigonometric Functi...
Trigonometry - Simple Identities What is a trigonometric identity? Trigonometric identities are statements that are true for all values of x or theta (θ) They are used to help simplify trig equatio...
