∫sinx/cosx√(5-4cosx)dx

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∫sinx/cosx√(5-4cosx)dx

∫sinx/cosx√(5-4cosx)dx
∫sinx/cosx√(5-4cosx)dx

∫sinx/cosx√(5-4cosx)dx
设√(5-4cosx)=t,则sinxdx=tdt/2
∴原式=∫(tdt/2)/[t(5-t²)/4]
=2∫dt/(5-t²)
=(1/√5)∫[1/(√5+t)+1/(√5-t)]dt
=(1/√5)[ln│√5+t│-ln│√5-t│]+C (C是积分常数)
=(1/√5)ln│(√5+t)/(√5-t)│+C
=(1/√5)ln│[√5+√(5-4cosx)]/[√5-√(5-4cosx)]│+C

∫sinx/cosx√(5-4cosx)dx
=-∫[1/cosx√(5-4cosx)]dcosx
cosx=t
=-∫[1/t√5-4t)]dt
=-1/5 * ∫[(5-4t)+4t]dt / [t √(5-4t)]
=-1/5 * ∫√(5-4t) dt/t -1/5* ∫4dt/√[(5-4t)]
5-4t=u
其他请自己完成