## 355 Reputation

8 years, 361 days

## partial integration hint?...

Maple 2018

Why can't maple integrate

restart;
`assuming`([int(GAMMA(a, s)*exp(-b*s), s = 0 .. infinity)], [b > 0, a > 0])

which has a simple result obtained by partial integration?

## Remove infinity from list...

Maple 18

How do I remove infinity from a list

s:=[f(x) , exp(a), GAMMA(2x)-1 , infinity , 1, -infinity]

remove(has,%,infinity)

does not work.

It should yield

s:=[f(x) , exp(a), GAMMA(2x)-1 , 1]

## Pulling power into exponential under ass...

Maple 15

Hello,

Simple question:

Why does

restart;

(exp(I*t))^q;

`assuming`([simplify(%)], [t > 0, t < 2*Pi, q > 0, q < 1])

not simplify to exp(I*t*q)

?

## Multiple Integration with badly behaved...

Maple 2015

restart;

with(VectorCalculus);

with(LinearAlgebra);

r1 := Vector([0, 0, 1]);

r2 := Vector([sin(theta1), 0, cos(theta1)]);

r3 := Vector([VectorCalculus:-`*`(sin(theta2), cos(phi2)), VectorCalculus:-`*`(sin(theta2), sin(phi2)), cos(theta2)]);

M := Matrix([r1, r2, r3]); ex := `assuming`([simplify(VectorCalculus:-`*`(Determinant(M), 1/VectorCalculus:-`+`(VectorCalculus:-`+`(VectorCalculus:-`+`(1, DotProduct(r1, r2)), DotProduct(r1, r3)), DotProduct(r2, r3))))], [theta1 > 0, theta2 > 0, phi2 > 0]);

dex := eval(simplify(diff(arctan(ex), phi2)), phi2 = t);

VectorCalculus:-`*`(2, Int(VectorCalculus:-`*`(VectorCalculus:-`*`(VectorCalculus:-`*`(2, Int(dex, t = 0 .. phi2)), 1/VectorCalculus:-`*`(4, Pi)), VectorCalculus:-`*`(VectorCalculus:-`*`(VectorCalculus:-`*`(VectorCalculus:-`*`(2, Pi), sin(theta1)), sin(theta2)), 1/VectorCalculus:-`*`(VectorCalculus:-`*`(VectorCalculus:-`*`(4, Pi), 4), Pi))), [phi2 = 0 .. Pi, theta2 = 0 .. Pi, theta1 = 0 .. Pi], method = _CubaCuhre, epsilon = 0.5e-2));

evalf(%)

Ok I deleted my other question, since there was a mistake. I actually want to integrate the following expression. The arctan is not every positive in my integral there, so I needed to go this way to make it continuous. The problem here is the nested integral inside Int(...,t=0..phi2) which leads to maple not being able to evaluate.

## build in sum, add with optional conditio...

Maple

Is there already a build in sum(), add() procedure where you can supply a condition?

I know the help doesn't say anything about it, but I thought maybe there is something else.

Say I want to add the coefficients a(n) up to N, but only if n divides N, so