Identities expressing trig functions in terms of their supplements Sum, difference, and double angle formulas for tangent The half angle formulas The ones for sine and cosine take the positive or negative square root depending on the quadrant of the angle θ/2 For example, if θ/2 is an acute angle, then the positive root would be used Truly obscure identities These are just here forThe sure way also stated that, uh, the rest of the trigonometry identities are just receptacles off the 1st 3 Right? Trigonometric Identities The distances or heights can be calculated using mathematical techniques that fall under the category of 'trigonometry'The word 'trigonometry' comes from the Greek words 'tri' (meaning three), 'gon' (meaning sides), and 'metron' (meaning measure) (meaning measure)
Summary Of Trigonometric Identities