CHAPTER 4. TRIGONOMETRY = = Figure 60. = 375. q~åÖÉåí=cìåÅíáçå= ó = í~å ñ I= ñ ≠ ( N ) â O + π I= ∞− ≤ í~å ñ ≤ K ∞ = O = = = Figure 61. = 83