CHAPTER 4. TRIGONOMETRY382. =
α°= αê~Ç= ëáåα= Åçëα= í~åα= Åçíα=NR=
NOπ
=
QS− O
=
Q
S+ O
= O− P= O+ P=
NU=
NM
π
=
QR−N
=
Q
NM+O R
R
R−O R
= R+O R=
PS=
R
π
=
QNM−O R
Q
R+N
=
R N
NM O R
+
−
NM O R
R N
−
+
=
RQ=
NM
Pπ
=
QR+N
=
Q
NM−O R
NM O R
R N
−
+
R N
NM O R
+
−
=
TO=
R
Oπ
=
QNM+O R
Q
R−N
= R+O R= R
R−O R
=
TR=
NO
Rπ
=
QS+ O
=
Q
S− O
= O+ P= O− P=
=
=
=
4.5 Most Important Formulas
=
ëáåOα+ÅçëOα=N=
ëÉÅOα−í~åOα=N=
ÅëÅOα−ÅçíOα=N=
α
α
α=
Åçëëáå
í~å =