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Let be $ \Sigma=\{0,1\}$ and $ L$ $ =$ $ \{u \in \Sigma^* :$ $ odd\ number\ of\ 0’s\ and\ odd\ number\ of\ 1’s\}$ . How Can I build a regular expression or an automata for this languaje? I have no idea, and I gess $ L$ is not regular, but I vane’t been ableRead more

I am badly stuck in some integration here and will appreciate any help out of it. $ $ \int^\infty_0f(r) dr = \int^\infty_0 \frac{Ar}{1+Cr^\alpha} e^{-Br^2} dr$ $ If I let $ u = Br^2$ , then I get $ $ = \frac{A}{2B} \int^\infty_0\frac{\exp(-u)}{1+(u/B)^{\alpha/2}} du$ $ But I am stuck while proceeding further. Any idea?Read more

I have a rather silly question, I assume: I have a (nested) list of polynomials that I made from a matrix with the Minors command and I would like to make them into polynomial equations with a conjunction. So for instance, say the list is equal to {{f1,f2},{f3,f4}}, where f1,f2,f3,f4 are polynomials, then I wantRead more

I am working on a problem that results in expressions with trig functions and their derivatives along with several other functions and derivatives. At one point, the subtraction of two expressions resulted in an expression proportional to 1 + sin”[x] / sin[x] whose value is obviously zero. How do I get Mathematica to evaluate theRead more

I want to create a function $ f$ which takes as a parameter a function $ h$ , and calculates its integral between $ a$ and $ b$ . But I want to apply memoization to this, by only calculating the integral the first time it is called for a particular function of $ h$Read more

I am trying to reduce the following trig expression $ $ \frac{\ln \left(\sin \left(\frac{\alpha x}{2}\right)+\cos \left(\frac{\alpha x}{2}\right)\right)}{\alpha }-\frac{\ln \left(\cos \left(\frac{\alpha x}{2}\right)-\sin \left(\frac{\alpha x}{2}\right)\right)}{\alpha }$ $ into $ $ \frac{\ln (\tan (\alpha x)+\sec (\alpha x))}{\alpha }$ $ I tried using TrigExpand, TrigReduce and FullSimplify with no use. CODE: FullSimplify[Integrate[Sec[\[Alpha]*x], x], Assumptions -> {\[Alpha] > 0 &&Read more

It’s a problem I encountered when answering this question and I think it’s worth starting a new question for it. Consider the following expressions: expr = Erfc[x/(2 Sqrt[t])] – E^(t + x) Erfc[Sqrt[t] + x/(2 Sqrt[t])]; texpr = E^(-Sqrt[s] x)/(s + s^(3/2)); texpr is the Laplace transform of expr when x > 0. This canRead more

I am using Mathematica to manipulate/keep tract of a long series of symbol manipulations. One thing that I would like to do is separate or order the terms of an expression by positive and negative sign. For example separating or something more simple that we can use as an example b+ c^2 -c^2 +a^4 -c^5Read more

How to use twig expression in Drupal 8 content field and render. If I embed following twig expression in field value {% if variable == 1 %} you are logged in {% endif %} When I render the field template I want to print “you are logged in”. Right now it renders as: {% ifRead more

What’s the most compact WL translation of this GLSL expression: length(max(vec2(x,y),s)) ?Read more