The Ungerecht Family Tree

45-45-90 triangle: hyp = side * √2 30-60-90 triangle: short side = a, long side = a*√3, hyp = 2a

area of a right triangle = 1/2*h*w

hypotenuse is the side opposite the right angle, opposite is the side opposite the given angle, adjacent is the side next to the given angle

SOHCAHTOA (Soak a toe-ah): Sin=Opp/Hyp, Cos=Adj/Hyp, Tan=Opp/Adj

law of sines:

sin(A)/a = sin(B)/b = sin(C)/c  (sometimes a/sin(A) = ...)

law of cosines - to find an angle when all the sides are known

cos(A) = (b² + c² - a²) / (2bc)
cos(C) = (a² + b² - c²) / (2ab), cos(B) is same pattern
  (side a is opposite angle A, etc)
rewriting it: c = √(a² + b² - 2abcos(C))

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