Hello, atwinix!

Could you restate the problem?

. . Your writing raises many questions.

I need help on solving the following equation. . . . . Equation?

∫ (π+t) cos (nt) dt + ∫ (π-t) cos (nt) dt

I don't know if it's clear but its like this:

"Integral of [(pi + t) into cos (nt)] dt + integral of [(pi - t) into cos (nt)] dt."

What does "into" mean?

If the problem is: .

. . why not make one integral?

. .