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http://en.wikipedia.org/wiki/Laguerre_polynomials

http://wenku.baidu.com/view/7d013c8c680203d8ce2f24ee.html  

how to evaluate to equation (5.9) in page 195 from rodrigues formula?

rodrigues := exp(x)*(x^alpha)/n!*Diff(exp(-x)*(x^(n+alpha)), x$n);
rodrigues := subs(x=2*p, rodrigues);
rodrigues := subs(alpha=1/2, rodrigues);

Hi, this  must have been asked numerous time, but I cannot find it in MaplePrimes:

How does one "collect" sqrt terms? collect(expression,sqrt) does not work because sqrt is actually represented as ^(1/2) in  Maple. collect on '^' does not work either... ??

Mac Dude

Hello everyone,

I like to force following:

a/(a+b) --->  1/(1+b/a)

I know that collect is a powerful tool that is actually capable of doing such things. In a similar (old) thread, it was suggested to use a function in the last part like

collect(expression, varialble, (x->something)@factor)

but I don't understand what exactly this means. Any help?

another related question is, is the collect command available as right-click option?

I have a rather large multivatiate polynomial "Dtest"  I need to divie it by a cubic poly "DGm" using rem and quo. Both are determinants multiplied out,  both given below. Have spent the past 2 nights trying to sort, collect, expand, equate coefficients plex groebner etc. Am trying to collect up all the powers of c₃ but cant anything to work. even expand doesn't fully expand "Dtest". If I set c₁ and c₂ to 1 things are...

I wrote the following MAPLE code

restart; N := 2

alias(epsilon = e, eta = t)

eq1 := 5*(diff(F(t), `$`(t, 3)))+(1+3*e)*F(t)*(diff(F(t), `$`(t, 2)))-(2+e)*(diff(F(t), t))^2 = 0

F := proc (t) options operator, arrow; sum('F[i](t)*e^i', 'i' = 0 .. N) end proc

deqn := simplify(collect(eq1, e), {e^(N+1) = 0})

MAPLE says

Error, (in sum) too many levels of recursion

How do I get this error corrected?

How may I program the following with Maple?

(1) Define the function:

H(p) := p * c1 + p^2 * c2 + p^3 * c3  + ......

(2) Now construct the following expression:

(1-p) [ v''' + 1 ]  = H(p) [ v''' - 25 * v' + 1]

Here, v is some funciton of x.

(3) Now assume: v = u0 + u1 * p + u2 * p^2 + ...

and substitute this into the expression defined at the point (2).

Hi there,

I got an output

and would like to bring it in the form

.

How do I do that? :)

In fact I don't even manage to collect the factor of 3*beta^2 as follows

Why does collect only work sometimes?

I will show with a simple example.  I can do this

a := 5*x^2-4*x+3;
       
                             a := 5 x²  - 4 x + 3
h := exp(x)*a+exp(x);
            ...

From this expression I want to extract only terms with the variable x.

F := (1/2/Pi+Q*cos(k*x))^2*(1/2/Pi+Q*cos(k*y))/(1+beta^2*(1/2/Pi+Q*cos(k*x))^2);

I don't want to manually write it out rather extract the terms programmaticallly. I want to be left with

(1/2/Pi+Q*cos(k*x))^2 / (1+beta^2*(1/2/Pi+Q*cos(k*x))^2)

I have tried the collect fucntion but that did not seem to do it. Any suggestions...