∫tan^3xdx+∫tan^5xdx,

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∫tan^3xdx+∫tan^5xdx,
∫tan^3xdx+∫tan^5xdx,

∫tan^3xdx+∫tan^5xdx,
答案其实很简单~~
∫tan^5x dx
=∫tan³x(sec²x-1) dx
=∫tan³xsec²x dx - ∫tan³x dx
∴原式=∫tan³x dx + ∫tan³xsec²x dx - ∫tan³x dx
=∫tan³xsec²x dx
=∫tan³x d(tanx)
=(1/4)tan^4x + C

原式=∫(tanx)^3[1+(tanx)^2]dx=∫[(sinx)^3/(cosx)^5]dx
=-∫[(sinx)^2/(cosx)^5]dcosx=-∫{[1-(cosx)^2]/(cosx)^5}dcosx
=∫[1/(cosx)^3]dcosx-∫[1/(cosx)^5]dcosx
=-1/[2(cosx)^2]+1/[4(cosx)^4]+C
=-[2...

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原式=∫(tanx)^3[1+(tanx)^2]dx=∫[(sinx)^3/(cosx)^5]dx
=-∫[(sinx)^2/(cosx)^5]dcosx=-∫{[1-(cosx)^2]/(cosx)^5}dcosx
=∫[1/(cosx)^3]dcosx-∫[1/(cosx)^5]dcosx
=-1/[2(cosx)^2]+1/[4(cosx)^4]+C
=-[2(cosx)^2-1]/[4(cosx)^4]+C
=-(1/4)cos2x(secx)^4+C

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