http://www.mapleprimes.com/posts/42325-Solve en-us 2026 Maplesoft, A Division of Waterloo Maple Inc. Maplesoft Document System Wed, 10 Jun 2026 19:52:11 GMT Wed, 10 Jun 2026 19:52:11 GMT The latest comments added to the Post, solve http://www.mapleprimes.com/images/mapleprimeswhite.jpg http://www.mapleprimes.com/posts/42325-Solve http://www.mapleprimes.com/posts/42325-Solve?ref=Feed:MaplePrimes:solve:Comments#comment79166 The description of applyop can be found in its help page, <code> ?applyop</code>. Your example is just a double integral. One doesn't need dsolve to evaluate it. Using applyop, it can be done as <pre>u:=1+sum((-1)^(i)*Heaviside(t-T[i+1]),i=1..n-1)+ sum((-1)^(i)*Heaviside(t-T[n+i]),i=1..n): value(map[3](applyop,student[Doubleint],1,u,t,t))/M; / /n - 1 | 2 |----- | t | \ i 2 |---- + | ) (-1) (1/2 Heaviside(t - T[i + 1]) t | 2 | / | |----- \ \i = 1 2 - 1/2 Heaviside(t - T[i + 1]) T[i + 1] - T[i + 1] ( Heaviside(t - T[i + 1]) t - Heaviside(t - T[i + 1]) T[i + 1]) \ / n | |----- | | \ i 2 )| + | ) (-1) (1/2 Heaviside(t - T[n + i]) t | | / | |----- / \i = 1 2 - 1/2 Heaviside(t - T[n + i]) T[n + i] - T[n + i] ( Heaviside(t - T[n + i]) t - Heaviside(t - T[n + i]) T[n + i]) \\ || || )||/M || || //</pre>If you want to avoid using applyop or double integral for some reason, then you could just do your manipulations with dsolve for every term (1 and expressions inside sums) and then add them manually. _________ Alec Mihailovs <a href="http://mihailovs.com/Alec/">http://mihailovs.com/Alec/</a> The latest comments added to the Post, solve 79166 Mon, 06 Nov 2006 00:41:31 Z alec alec