Question

求不定积分：sin x的四次方比上cos x的八次方

Answer 1

sin x的四次方比上cos x的八次方dx
=[(tanx)^4]*[(secx)^2]^2dx
=[(tanx)^4]*[(1+（tanx)^2]*(secx)^2dx
=[(tanx)^4]*[(1+（tanx)^2]d(tanx)
=[(tanx)^4]d(tanx)+（tanx)^6 d(tanx)
=1/5(tanx)^5+1/7（tanx)^7+C