Substitution step: Let's do a substitution: let u=1−x, then du=−dx.
Change limits: Change the limits of integration. When x=0, u=1. When x=1, u=0.
Substitute in terms of u: Substitute everything in terms of u. The integral becomes −∫10cos(π/u)u−2du.
Flip limits: Flip the limits of integration to get rid of the negative sign. The integral is now ∫01cos(π/u)u−2du.
Integrate with respect to u: Now, integrate cos(uπ)u−2 with respect to u. This is not a standard integral and cannot be solved using elementary functions.
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