TRIGONOMETRY LAWS AND IDENTITIES DEFINITIONS sin(x)= Opposite Hypotenuse cos(x)= Adjacent Hypotenuse tan(x)= Opposite Adjacent csc(x)=TRIGONOMETRIC IDENTITIES Reciprocal identities sinu= 1 cscu cosu= 1 secu tanu= 1 cotu cotu= 1 tanu cscu= 1 sinu secu= 1 cosu Pythagorean Identities sin 2ucos u= 1 1tan2 u= sec2 u 1cot2 u= csc2 u Quotient Identities tanu= sinu cosu cotu= cosu sinu CoFunction Identities sin(ˇ 2 u) = cosu cos(ˇ 2 u) = sinu tan(ˇ 2 u) = cotu cot(ˇ 2 u) = tanu csc(ˇ 2 u) = secu sec(ˇ 2 u) = cscuSin 2t = 2 sin t cos t cos 2t = cos 2 t – sin 2 t = 2 cos 2 t – 1 = 1 – 2 sin 2 t Less important identities You should know that there are these identities, but they are not as important as those mentioned above They can all be derived from those above, but sometimes it takes a bit of work to do so The Pythagorean formula for tangents
What Are The Quotient Identities For A Trigonometric Functions Socratic
