If you had say ∫cos(adsbygoogle = window.adsbygoogle || []).push({}); ^{4}(x)dx according to my integration table in calc book this would be something nasty. Could you not say let u = sin^{5}(x)/5 therefore du = cos^{4}(x)dx and then ∫du = u = sin^{5}(x)/5 + C. Is there something wrong with this. This technique would work on ∫x^{2}if you said let u = x^{3}/3 and then did everything else the same except there its not quite so tricky. I guess what I'm asking is if you're good at designing a function that when differentiated would give the funtion in the integral can you use my method there instead of the tables which give this nasty formula: ∫cos^{n}(x)dx = [(cos^{n-1}x)(sinx)]/n + [(n-1)/n]∫cos^{n-2}(x)dx

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Integration Question

**Physics Forums | Science Articles, Homework Help, Discussion**