作者:Mai Truong 1 年以前
147
更多类似内容
tanθ=1/cotθ and cotθ=1/tanθ
cosθ=1/secθ and secθ=1/cosθ
sinθ=1/cscθ and cscθ=1/sinθ
Pythagorean Identities
〖csc〗^2 θ-〖cot〗^2 θ=1^
〖sec〗^2 θ-〖tan〗^2 θ=1^
〖sin〗^2 θ+〖cos〗^2 θ=1^
Half Angle Identities
tan^2(θ) = (1 - cos2θ) / (1 + cos2θ)
cos^2(θ) = (1 + cos2θ)/2
sin^2(θ) = (1 - cos2θ)/2
Double Angle Identities
tan2θ = 2tanθ / 1 - tan^2(θ)
cos(2θ) = 1 - 2sin^2(θ)
cos(2θ) = 2 cos^2 (θ) - 1
cos(2θ) = cos^2(θ) - sin^2(θ)
sin(2θ) = 2sinθ cosθ
Sum/Difference Identities
tan(α±β) = (tanα ± tanβ)/(1 ∓ tanαtanβ)
cos(α±β) = cosα cosβ ∓ sinα sinβ
sin(α±β) = sinα cosβ ± cosα sinβ
Cofunction Identities
csc(π/2-θ)=secθ and sec(π/2-θ)=cscθ
tan(π/2-θ)=cotθ and cot(π/2-θ)=tanθ
sin(π/2-θ)=cosθ and cos(π/2-θ)=sinθ
Even/Odd Identities
sec(-θ)=secθ
csc(-θ)=-cscθ
cot(-θ)=-cotθ
tan(-θ)=-tanθ
sin(-θ)=-sinθ
cos(-θ)=cosθ
Product to Sum
cosα sinβ=1/2 [ sin(α+β) - sin(α-β) ]
sinα cosβ=1/2 [ sin(α+β) + sin(α-β) ]
cosα cosβ=1/2 [ cos(α-β) + cos(α+β) ]
sinα sinβ=1/2 [ cos(α-β) - cos(α+β) ]
[-1,+1]
tanθ
(-∞,+∞)
secθ
R-(2n+1)π/2
cscθ
2π
(-∞,-1]∪[+1,+∞)
cotθ
Period
π
R-nπ
[-π/2, π/2]
[0, π]
[-1,1]
〖tan〗^(-1) x= θ
(-π/2, π/2)
〖sin〗^(-1) x= θ
[0, π], θ≠π/2
〖csc〗^(-1) x= θ
[-π/2, π/2], θ≠0
(-∞,-1]∪[1,+∞)
〖cot〗^(-1) x= θ
Range
(0, π)
Domain
(-∞,+∞)