## Trigonometric Equations

Skill Type Description Source
The Addition Formulae Booklet This unit details the addition formulae for sin(A+B), sin(A-B), etc MathsCentre
4.2 Trigonometric Functions Workbook express angles in radians + define trigonometric functions generally + sketch the graphs of the three main trigonometric functions: sin, cos, tan HELM
Cosecant, Secant and Cotangent Booklet This unit explains what is meant by these three trigonometric ratios. Graphs of the corresponding functions are provided MathsCentre
The Double Angle Formulae Booklet This unit looks at the trigonometric formulae known as the double angle formulae MathsCentre
4.4 Applications of Trigonometry to Triangles Workbook Use trigonometry in everyday situations + fully determine all the sides and angles and the area of any triangle from partial information HELM
a cos x +b sin x = Rcos(x-a) Booklet In this unit we explore how the sum of two trigonometric functions can be expressed as a single trigonometric function MathsCentre
4.5 Applications of Trigonometry to Waves Workbook use simple trigonometric functions to describe waves + combine two waves of the same frequency as a single wave in amplitude-phase form HELM
Trigonometric Equations Booklet This workbook explains how a number of trigonometric equations can be solved by making reference to a Table of standard results and using the symmetries and periodicities present in the graphs of trig functions MathsCentre
Trigonometric Identities Booklet In this unit several identities are derived and then used in the solution of trigonometric equations MathsCentre
Trigonometrical Identities Worksheet This leaflet lists a number of commonly used trigonometrical identities MathsCentre
a cos x + b sin x = R cos(x - α) Video - 29 mins In this unit we explore how the sum of two trigonometric functions e.g. 3 cos x + 4 sin x, can be expressed as a single trigonometric function. Having the ability to do this enables us to solve trigonometric equations and find maximum and minimum values MathTutor
Cosec, sec and cot Video - 16 mins In this unit we see how the three trigonometric ratios cosecant, secant and cotangent can appear in trigonometric identities and in the solution of trigonometric equations. Graphs of the functions are obtained from a knowledge of sine, cosine and tangent MathTutor
The addition formulae Video - 27 mins There are six so-called addition formulae often needed in the solution of trigonometric problems. In this unit we start with one and derive a second. Then we take another one as given and derive a second one from that. Finally we use these four to help us MathsCentre
The double angle formulae Video - 26 mins Double angle formulae are so called because they involve trigonometric functions of double angles e.g. sin 2A, cos 2A and tan 2A MathTutor
Triangle formulae Video - 40 mins A common mathematical problem is to find the angles or lengths of the sides of a triangle when some, but not all, of these quantities are known. It is also useful to be able to calculate the area of a triangle from some of this information MathTutor
Trig equations Video - 44 mins The strategy we adopt in solving trigonometric equations is to find one solution using knowledge of commonly occurring angles and then use the symmetries in the graphs of the trigonometric functions to deduce additional solutions MathTutor

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