# Items tagged with simplifysimplify Tagged Items Feed

### Simplify a system of ODEs...

February 06 2016
2 3

Can Maple simplify these DE's by eliminating the d/dt VL(t) by taking the derrivative of the bottom equation and substituting in the first one?

February 06 2016
0 13

In this question, I asked for a way to simplify an expression containing radicals. The discussion led us to that as default field for simplicfication is the Complex number system we should use assume or assuming command to simplify the radicals. However, the mothod suggested there seems to not work in this new case that I have. For details please see the attached file. The terms sqrt{u} and sqrt{u-1} should cancel in denominator.

What Maple Does

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Remark by Markiyan Hirnyk. The below content is added by the questionner on 08.02.2016 .

What Mathematica Does

### How to simplify product of exponentials?...

January 26 2016
4 14

I assume that I'm not providing the correct input to the simplify command to get the simplification that I want.  In particular, for the following code:

assume(n, positive);
simplify(3^(-(1/2)*n)*2^((1/6)*n)-2^((2/3)*n)*6^(-(1/2)*n));
simplify(log(3^(-(1/2)*n)*2^((1/6)*n))-log(2^((2/3)*n)*6^(-(1/2)*n)));

The expression should evaluate to 0.  However, the first expression does not simplify to 0 (it does not simplify at all in Maple) while the second expression simplifies to 0.

The simplification is fairly easy for the first expression by factoring 6 and combining terms; it seems like I'm not entering the command to simplify in this way.

January 24 2016
0 11

I have the following expression

f=u/(sqrt(u*(u-1)))

and I want to simplify it. Eventhough that I tell Maple that u is real and greater than 1 but it does not simplify the expression. What is wrong? Please see the attached file.

### How to optimize this code?...

January 24 2016
0 9

a1:= f(x) :
> T1 :=simplify((taylor(a1,x=alpha,N+3))):
> E1:=subs([seq(((D@@i)(f))(alpha) = 0,i=1..m-1),f(alpha)=0,x=e[n]+alpha],T1):
> g1 :=(convert(simplify(series((E1,e[n]=0,N))),polynom));

### `assuming` not working for functions...

January 12 2016
0 2

This is a stripped down example of something I've been doing. Basically I'm building matrices which I then, using unapply, convert into functions of some variables of t.
.... but found that simplify seems to often not work as i'd wish.

restart:
mm:=Matrix([[cos(sqrt(g__1^2)*t), (-I*g__1*sin(sqrt(g__1^2)*t))*(1/sqrt(g__1^2))], [(-I*g__1*sin(sqrt(g__1^2)*t))*(1/sqrt(g__1^2)) ,cos(sqrt(g__1^2)*t)]]);

#great - simplifies as i'd expect:
simplify(mm) assuming g__1::positive;

Do the same thing but when matrix is a function of t
mmFun:=unapply(mm, t);

#the function works - gives what i'd expect
mmFun(3); mmFun(t);

#but now the simplification does not work - why the g__1 in the argument of cos does not get properly simplified?
simplify(mmFun(t)) assuming g__1::positive;

Any ideas if this is a bug? I'm using maple 2015.2 on linux 64-bit.

here is the worksheet: simplify_issue.mw

thanks

EDIT:

as a side note once can sometimes overcome this with mapping simplify  as in :

map(simplify, resultMatrix ) assuming g__1::positive;

but this is not optimal, and sometimes does not work when i first multiply the matrix by say a vector.

### Sequence of values of given funciton...

December 31 2015
0 8

Dear all,

Thank you for helping me  to generate a table of values of f(x) starting with x=0 to 100 in steps of 1, that is for x=0,1,2,3,...,100.

I tried:

f:=x->2*sqrt(3)*a1*a2*(sum(pochhammer(1/3,k)*3^k*x^(3*k)/(3*k)! ,k=0..infinity)*sum(pochhammer(2/3,k)*3^k*x^(3*k+2)/(3*k+2)!  ,k=0..infinity)-sum(pochhammer(2/3,k)*3^k*x^(3*k+1)/(3*k+1)!  ,k=0..infinity)*sum(pochhammer(1/3,k)*3^k*x^(3*k+1)/(3*k+1)!  ,k=0..infinity));

tab_values:=[evalf(simplify(seq(Ni1(xx),xx=0..100)))];

But I the result is amazing.... I don't understand the problem.

Thanks

### Simplification question...

December 22 2015
0 5

I have a polynomial expression that I would like to cast into a specific form. The expression is

and I know that it can be simplified into a form involving squares of (A[Qi]-Pi). It is trivial to do this on paper; how can I convince Maple to do this.

The solution I came up with was to use mtaylor and expand about the forms I know to be there:

mtaylor((3),[A[Q1]=P1,A[0]=P2*rho/(rho+Q1),A[Q3]=P3],6);

which is what I want (close to, anyway). Now, I consider this to be a bit of a dirty trick that works here as the expression is simple and no higher-order terms are present so in fact the solution is exact. But, are there methods along simplify and friends that can do this? I have not been successfull with those...

This is a part of a much longer worksheet and part of a lecture, so I need Maple to be able to do this. The mtaylor trick works, but I would not want to miss an obvious approach that may work where mtaylor would get confused.

Thanks,

M.D.

test.mw

### How to find exact value of it?...

December 16 2015
0 5

I try to find the exact (symbolic) value of

(-2*sqrt(7)-4)*EllipticK((1/8)*sqrt(2)*(-3+sqrt(7)))^2+4*EllipticE(-(1/8)*sqrt(2)*(-3+sqrt(7)))*sqrt(7)*EllipticK((1/8)*sqrt(2)*(-3+sqrt(7)))

I tried 'simplify' with different options and 'convert'. It would be pi=3.141... as numerical approximation suggests.

Many thanks.

### How to obtain this representation?...

December 10 2015
0 2

It is given

xn (n x - n - x) / (x-1)2 + x / (x-1)2  , n is a (symbolic) positive integer.

I want to transform it into

n xn+1 / (x-1) - x (xn-1) / (x-1)2

How is it possible?

I tried the  simplify, convert (parfrac), collect, combine, expand,  with/without assuming.

### Why error in simplify?...

December 07 2015
0 3

why is simplify is making errors - me or maple?

Ec := (1/2)*Kc*(2*Pi*h0/Pi(a0^2+h0^2)-2*Pi*h/Pi(a^2+h^2))^2;
2
1 / 2 Pi h0 2 Pi h \
- Kc |------------- - -----------|
2 | / 2 2\ / 2 2\|
\Pi\a0 + h0 / Pi\a + h //
simplify(%);
2
2 Kc (-h0 + h)

Simplify is erasing the varibles a0 and a. Is there a secret to using simplify?

### Simplify to a specific form...

November 20 2015
1 2

The two forms below (eqn1 and eqn2) give the same result. You can convert from eqn1 to eqn2 using the expand option but is there a way can you get Maple to simplify eqn2 back to eqn1?

( I have tried all the simplify options I know)

eqn1:=

eqn2:=

Thanks.

### How to simplify certain terms of it?...

November 19 2015
0 2

hi,

here a comlicated formula,how i simplify

thanks  a lot.

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f is a complicated function,i want to make it more simplify,but i want to keep square style,

let coefficients of X and Y keep one unit,and simplify terms  containd special symbol of omega

it what i wanted.

### Matrix differentiation...

November 11 2015
1 2

Hello,

I am trying to differentiate a matrix containing four variables, alpha, alphaB (representing alpha bar), beta, and betaB (for beta bar). They are are variables with respect to t. I then need to let t=0 and then simplify the result with some initial conitions i have. Could you tell me any useful maple functions which i can use to do this? If you need anymore information let me know and thank you for helping me.

Robbie

### How to simplify it?...

November 09 2015
1 1

can someone tell me how can I derive and solve d(g1(x))=0 a complicated function as

I tried with the instructions simplify and combine but without results.