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cos(-@) = cosa sin(—œ) = — sin œ
tan(-œ} = — tan œ
cot(—œ) = —cot œ
sin(Z — œ) = sin œ
€OS(Z-œ — —cosœ tan(z-a) = — tana
cot(z — a) = —cota
sin(œ + Z) = — sin œ COS(Œ + 7£) = —COSŒ tan(a@ + Zz) = tan œ cot(a + 7) =cota
sin(Z — a) = cosa
2
cosC CS — «x3 — sina >
a
tan( — — œ) = coi œ
Ee
cos” ø +sin” ø =1
1+tan?ø= a+ tks, keZ
L+cot? a= mm azka, keZ
sma
tana.cota =1 c, keZ
cos(a —b) = coszcos b + sin zsin b cos(a + b) = cosacosb — sinasinb
sin(a —b) = sinacosb —sinbcosa
sin(a + b) = sin acosb + sinbcosa tan(a—b) = tana—tanb
1+tanatanb tan(a +b) = tana+tanb
1—tan atanb
sin 2a = 2sin acosa
©0824 = cos” a—sin’ a= 2c0s’ a-1=1-2sin’a
cosacosb= 5 leosta +b) +cos(a—b)]
sinasind => [cos(a +b) —cos(a —b)]
sinacosb= ; [sin@+ b) + sin@—b)]