Trig Identities and other Formulas

  1. Sin (a + b) =
    Sin(a) Cos(b) + Sin(b) Cos(a)
  2. Sin (a – b) =
    Sin(a) Cos(b)- Sin(b) Cos(a)
  3. Cos (a + b)=
    Cos(a) Cos(b) – Sin(a) Sin(b)
  4. Cos(a – b)
    Cos(a) Cos(b) + Sin(a) Sin(b)
  5. tan(a + b)
    • tan(a) + tan(b)
    • 1− tan(a) tan(b)
  6. tan(a - b)
    • tan(a) + tan(b)
    • 1− tan(a) tan(b)
  7. sin2x + cos2x =
    1
  8. 1 + tan2x =
    sec2x
  9. 1 + cot2x =
    csc2x
  10. sin 2u =
    2sin(u) cos(u)
  11. cos2u =
    cos2u − sin2u
  12. sin ( θ/2 )=
    = ± squrt((1− cosθ)/2)
  13. cos( θ/2 )=
    = ± squrt((1− cosθ)/2)
  14. tan ( θ/2 )=
    • 1− cosθ
    • sinθ

    • sinθ
    • 1 + cosθ
  15. sinθ=
    y/r
  16. cosθ =
    x/r
  17. tanθ =
    y/x
  18. cscθ =
    r/y
  19. secθ =
    r/x
  20. cotθ =
    x/y
  21. 180o/π = π/180
    1
  22. sector =
    α r
  23. Area of a sector of a circle with angle α
    A S= αr 2/ 2
  24. Angular velocity
    ω = α / time
  25. Linear velocity
    ν = s/t = αr/t = rω
Author
hideeem
ID
115364
Card Set
Trig Identities and other Formulas
Description
Math 112 formulas
Updated