# simplifying-expressions's questions - English 1answer

1.283 simplifying-expressions questions.

### 2 What is the acceptable error in numerical calculations? [on hold]

I am doing a calculation where I try to simplify a very complicated complex function. I did this step by step and I checked that the numerical values that the function gets for certain values of the ...

### 1 “Simplify” or “Evaluate” an expression until it is expreseed in terms of some other variables

Let's say we have the following relation between different variables: ...

### 7 How to “rationalize” a fraction in Mathematica

When I try to rationalize the following number $$1\over{2^{1/4}+4^{1/4}+8^{1/4}}$$ FullSimplify[1/( 2^(1/4)+4^(1/4)+8^(1/4) )]I get the same expression, and ...

### Expression involving trig functions not simplifying

I have a complicated function that returns a fairly simple result:Sqrt[1/Abs[Sec[t/2]]^2 + Sin[t/2]^2]I can see that this is equal to one, but when I try to ...

### Evaluate an expression in terms other variables when lots of equations are involved

Unless I misunderstood something, this is different from a similarly worded question because I am not asking for the relationship between different variables here. I want to convert an expression ...

### Express variable in terms other variables when lots of equations are involved

Consider the following equations:W*BP == X*PC Y*AQ == Z*BQ AC^2 == AB^2 + BC^2 PQ^2 == BP^2 + BQ^2 AP^2 == AB^2 + BP^2 BC == BP + PC AB == AQ + BQLet's say, I ...

### 1 Can Simplify TransformationFunctions make multiple or branching suggestions?

Imagine, as a simple toy example, that it's valid to replace some list with any one of its elements. How could I write this into Simplify ...

### 1 Collect doesn't work properly

I run Want to write an expression in the form of expr= (b rr^w+ q rr^v +...)/(c rr^n + p rr^m + d rr^s +...)To do that, I write ...

### 3 Implementing a Schouten identity

1 answers, 125 views simplifying-expressions replacement
So I have an identity which looks like this: $\langle ij \rangle\langle kl \rangle + \langle ik \rangle\langle lj \rangle = \langle il \rangle\langle kj \rangle$ In mathematica I implement the angle ...

### 1 Collect/Expand with D

I am new to MMA and have a basic question. I am trying to separate the derivatives of an expression for simplification. E.g. on doing ...

### 2 Imaginary part of a function

So, I have the following:Simplify[Im[1/(-1 + Cos[θ])^2], Assumptions -> {θ -> Reals, 0 < θ < π}]which should evaluate to 0, as the function is ...

### Simplify not simplifying expression involving square roots of squares [closed]

I have a complicated function that is returning a simple expression. The symbols a and b are unassigned. I have not been able to get Mathematica to simplify the expression. (This is only a simple ...

### 16 What are the default TransformationFunctions used in Simplify and FullSimplify?

If I doSimplify[(c^3 - s^3)^2 - (s^3 + c^3)^2, TransformationFunctions -> Automatic](i.e. a verbose version of default behaviour), what transformation ...

### 2 What Transforming Functions does Simplify use? [closed]

Edit: Turns out in my use case I should use ComplexExpand instead of Simplify. My broader question is still worth answering, but ...

### 2 How to expand nested Abs

I want to expand this:FullSimplify[Abs[1 - Abs[x]], x \[Element] Reals]how can I do this? Evidently this function can be presented as ...

### Why won't Mathematica Conjugate this expression>

I've been trying to replicate the derivation of Bloch's equations in Mathematica and for the final substitution, it won't correctly conjugate the expression even though I specify that all of the ...

### 3 Getting around symbol favoritism of Simplify and FullSimplify [duplicate]

2 answers, 61 views simplifying-expressions assumptions
Simplify may or may not simplify depending on the symbols you use for its assumptions are good. For example, here is a case where ...

### rewriting negative powers

I often run into the problem that Mathematica refuses to simplify divergent subexpressions as part of a full expression that is manifestly finite. This only happens when a symbolic power is involved. ...

### 26 Is it possible to get this 'nicer' solution for an integral from Mathematica?

I'm on 11.3.0 for macOS (64-bit). On a recent CAS-enabled exam question a few weeks ago I was required to evaluate the following integral: $$\int_0^5\left(\sqrt[3]{125-x^3}\right)^2\,dx$$ In ...

### Simplifying huge expressions

I want to simplify a huge expression. There are many terms like in form as below in my huge expression. ...

### 4 use Range to form a vector

2 answers, 122 views simplifying-expressions iterators
I have a functiony[k_]:={0,0,0,I*t^k};and I need to get a vectorJoin[y[1],y[2],y[3],y[4],y[5],y[6],y[7]]and it is just ...