function - How can i calculate such integral in maple?

Question

Beloew Hyperlink shows Orthogonal Functions. I used different commands in maple but i can't apply these Integral expressions in Maple. How can i integrate such conditional Integrals ??? (For Example the Integral with red box around it)

Orthogonal Functions

Answer 1

(This is more of a math Question than a programming Question, so it probably should've gone to math.stackexchange.com.)

You need to use an assuming clause to tell Maple that m and n are integer, and you need to use option AllSolutions to int to tell it to do a case-by-case analysis of the parameters. For example,

int(sin(n*Pi*x/L)*sin(m*Pi*x/L), x= 0..L, AllSolutions) 
     assuming n::posint, m::posint, L>0;

I've assumed positivity of all parameters simply to reduce the number of cases presented in Maple's answer.