Strategy for Further Trigonometric Equations How to approach solving harder trig equations You can solve harder trig equations, such as those involving reciprocal and inverse functions in a variety...
R addition formulae Rcos Rsin etc How can I simplify expressions like a sin x ± b cos x or a cos x ± b sin x? If a and b are positive constants, then a sin x + bcos x can be rewritten as R sin (x ...
Double Angle Formulae What are the double angle formulae? The double angle formulae are derived from the 'A+B' versions of the compound angle formulae: Exam Tip The double angle formulae are...
Compound Angle Formulae What are the compound angle formulae? There are six compound angle formulae (also known as addition formulae), two each for sin, cos and tan: For sin the +/- sign on the lef...
Inverse Trig Functions What are arcsin, arccos and arctan? These functions are the inverse functions of sin, cos and tan sin (arcsin x) = x cos (arccos x) = x tan (arctan x) = x The domains of sin,...
Trigonometry - Further Identities What identities do I need to know with secant, cosecant, and cotangent? There are two identities with sec, cosec and cot that you need to know and be able to use: ...
Reciprocal Trig Functions - Graphs What does the graph of the sec look like? The graph of y = secx looks like this: y-axis is a line of symmetry has period (ie repeats every) 360° or 2π radians ver...
前几天UCAS发布了2022-23年申请季截止10月15日的申请数据报告！UCAS申请系统有两轮申请截止日期，第一轮是在10月15日截止，英国其他院校在此时间节点后也依然接受申请材料。 根据最新的UCAS数据，我们发现了以下“...
北京时间2022年10月19日，大学理事会正式开放SAT机考的国际报名，全新SAT机考的备考资源也已上线。从2023年开始，美国以外的所有SAT考试都将转为机考，美国SAT考试将在2024年全面转为机考。 2022年1月，大学理事...
Reciprocal Trig Functions - Definitions What are the reciprocal trigonometric functions? There are three reciprocal trig functions corresponding to the three regular trig functions Cotangent can al...
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° ...
