* TRIG *

* TRIG *

1. Cosine rule - c2 = a2 +b2-2ab cos (c)

2. are of a triangle is 1/2 absin(c) for if u dont know height otherwise its 1/2 base * height

3. Sine rule

   • The law of sines is how u relate the sides to the angles of any triangle so it doesnt have to be right angled
   • If a,b and c are lengths of sides opposite the angles A,B,C ina a triangle then a=b=c sinA =SinB= SinC

4. The sides are given names

   • the adjacent is the one left or as in the name is adjacen to the angle
   • The opposite is opposite the angle under consideration
   • The hypotenuse is the longest side and always opposite the right angle

5. There are 3 Formulas involved in Trigonometry

   • Sin - opposite/ hypotenuse
     • Cos - adjacent / hypotenuse
   • Tan - opposite/ adjacent

6. to remember the formulas use SOCAHTOA