How can i find a power series for this integral?

sportlover36
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how can i find a power series for this integral? \int cos(x^3)
 
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Hi sportlover36! :smile:

(have an integral: ∫ and a sigma: ∑ and try using the X2 tag just above the Reply box :wink:)

Just write out the series for cosx, and then write x3 everywhere instead of x. :smile:
 
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