M May Soh Cah Toa X Y X Y X Y X Y X Y (x,y) x y r sin = yryr cos = xrxr tan = yxyx 0 < < 9090 < < < < < < 360 sin > 0 cos > 0 tan > 0 sin > 0 cos < 0 tan < 0 sin < 0 cos < 0 tan > 0 sin < 0 cos > 0 tan < Allsintancos All + sin + tan + cos +
M May X Y AS TC 1 1 √2 sin45˚ = cos45˚ = tan45˚ = 1 √ 2 1 √ ˚ 60˚ 30 ˚ sin60˚ = cos60˚ = tan60˚ = √ √ 3 1 sin30˚ = cos30˚ = tan30˚ = 1 2 √ √ CAST diagram key angle X Y
M May Right angled triangle Pythagoras’ theorem Soh Cah Toa c a b c 2 = a 2 + b 2 sin = a /c cos = b /c tan = a /b The Sine Rule A C B a b c a sinA b sinB c sinC == sinA a sinB b sinC c = = The Cosine Rule a 2 = b 2 + c b c cosA b 2 = a 2 + c a c cosB c 2 = a 2 + b a b cosC b 2 + c 2 - a 2 2 b c =cosA