∫(9tan5x+7tan3x)(1+tan2x)dx(tan3x+tanx)12 =…
2(tanx)52+c
2(tanx)72+c
2(tanx)72|secx|+c
None
t=tanx,dt=sec2x dt ∫(9t5+7t3)dt(t3+t)1/2 ∫9t8+7t6(t9+t7)1/2dt y=t9+t7
⇒∫dyy⇒2y+c