# simplifying-expressions's questions - English 1answer

1.324 simplifying-expressions questions.

### 5 Issue with Upvalues

I want to introduce two variables (I call them EXt and EXtC, where "C" stands for complex conjugate) which would mimic the behavior of a phase of a complex number. For that, I use the following tags: ...

### 9 Mathematica can't simplify some logarithmic expressions

When I simplify some logarithmic expressions in Mathematica, it just returns the expression ...

### How to assume lexicographical ordering

Suppose I have functions which depends on the symbols $c[I]$, where $I$ is some subset of $\{1,2,...,n\}$. For example, $$f = c[1] + c[1,2,3] + c[1,2],$$ $$g = c[2] + c[2,1],$$ Code: ...

### 1 Pulling out a prefactor from a dot product

2 answers, 199 views simplifying-expressions tensors dot
I have three complicated vectors u, v and w as well as three simple prefactors ...

### Simplify not working, or ignoring assumption?

2 answers, 85 views simplifying-expressions assumptions
I'm trying to take a (-1) from a power to 3/2 as this:Simplify[(-(a))^(3/2) - ((-1)^(3/2) (a)^(3/2)), a > 0]I get as a result as expected 0. But when I try ...

### Collect terms with same-kind coefficients and factor exponential based on that

In the following expression, how can I group apart the terms in the exponential with a and b coefficients so that I can express ...

### 1 Help Simplifying Expressions

0 answers, 37 views functions simplifying-expressions
I have the following set of equations: 1) $\text{$b_1$} \cos (\text{$\beta_1$} u)-\text{$b_1$} \cosh (\text{$\beta_1$} u)-\text{$b2$} \cos (\text{$\beta_1$} \theta y)-\text{$d_2$} \cosh (\text{$\...

### 1 How to find and verify relationships between functions?

MMa gave me a complicated result involving Hypergeometric0F1's. It was much less complicated after I discovered this identity: ...

### 10 Remove Abs from Norms of Vectors

I have the following normNorm[{a, b*c}] (* Sqrt[Abs[a]^2 + Abs[b c]^2] *)How do I remove the Abs from it? ...

### 1 Eliminating Gamma from result of integration

I think the following integration result can be shown without Gamma. Can anyone explain Why Mathematica Uses Gamma. How to ...

### How do I separate 2 variables to be independent from each other in the equation?

I have an equation namely ...

### FullSimplify of Dirac Delta Function failed

I have t1 and t2 whose difference should be 0. But ...

### 4 Simplify behavior: assumption as Interval versus assumption as bounds

I am using MMA V11.2 under Linux I am surprised by this: ...

### 7 Finding sub-expressions that simplify larger formula

2 answers, 66 views simplifying-expressions symbolic
If I use FullSimplify on a large formula it will consequently return a much smaller expression. However, suppose I notice the simplified expression can benefit from ...

### Simplifying a solution of an equation

I have a linear system, this way: ...

### 7 Mathematica Not Interpreting Free Parameters Correctly

2 answers, 90 views simplifying-expressions symbolic
Forgive me if this has an obvious answer, but I've run into seemingly the same problem in a few different contexts now. When I evaluate expressions using different variables, all of which show up as ...

### 1 Make a term appear in my solution

1 answers, 44 views simplifying-expressions system
There is a solution for a linear system: ...

### Is $\frac{\log \left(\frac{1}{a}-1\right)+\log \left(-\frac{a}{a-1}\right)}{\log (10)} = 0$? [closed]

I have the following function, which for all values of $a$ is exceedlingly close to 0:(Log[-1 + 1/a] + Log[-(a/(-1 + a))])/Log[10] However, it does not ...

### 4 Recursively turn expression into nested list

I've been trying to write a simple function that turns an expression into a nested list. So for example, a+2b+3c becomes {a,{2,b},{3,c}}. This is what I wrote: ...

### 1 Modify the function Simplify

1 answers, 37 views functions simplifying-expressions
When I use Simplify with equations, the function simplifies both sides of the equation, for example: ...

### 6 How to speed up evaluation of expression (multiple variables) to gain speed? Compile?

I obtained some long expression and need to use them with a lot of different parameters inside a simulation. However, evaluation of the expressions is pretty slow, so that I would like to speed it up. ...

### 1 Problem with particular simplification of complex function under assumptions

I have proven that $expr=(1 - i)(\dfrac{1+z}{1-z})^{1/4}\dfrac{\sqrt{ 1-z^2+i z\sqrt{1 - z^2}}}{1+z-i\sqrt{1 - z^2}}=1$ when it is assumed that $z\in R$ and $|z|<1$ and when I also plot the real ...