Evaluate : ∫3x2+sin6xx+cos6xdxAnswer: 61log3x2+sin6x+CSolutionPut t=3x2+sin6x, so dt=(6x+6cos6x)dx=6(x+cos6x)dx, i.e. (x+cos6x)dx=6dt. Then61∫tdt=61log∣t∣+C.61log3x2+sin6x+CCBSE Class 12 Board · 2008 · Subjective