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10h
revised to simplify the following combinatorial terms
mathjax included
10h
suggested approved edit on to simplify the following combinatorial terms
12h
answered I can't understand how to factor a quadratic
13h
comment I can't understand how to factor a quadratic
Multipying out the two brackets you get $r^{2}+14r-3r-42 = r^{2}+11r-42$ as desired.
13h
comment First order moment of multivariate Gaussian random vector
Probably because the question shows little effort on your part. For example; what do you think, what was your attempt, what do you not understand etc...?
14h
comment Simplifying a Complex Number
You're missing a factor of $ 1/ \sqrt{2}$ from mulitplying both numerator and denominator of $(1+i)^{-1}$ by it's conjugate. In any case,, maybe de Moivre's theorem would help.
1d
comment Compute the double Hodge star operator
Think of $u=e_{1} \wedge \ldots \wedge e_{k}$ , where $e_{1} \ldots e_{k}$ are orthonormal . What are both $*u$ and $**u$?
1d
comment Trig and derivatives: If condition holds for derivative, does it hold for the original equation?
Your derivative is wrong, if you differentiate wrt to $x$ (assuming $y=y(x))$ then you would get $\cos x=\frac{dy}{dx} \sin y$. In general, to your further point, the answer is no.
1d
comment How to find the number of values for $x$ and $y$?
@5xum It's a way, perhaps not the best but it's still a valid way.
1d
comment How to find the number of values for $x$ and $y$?
All of the pairs $(x, y)$ lie on the straight line given by $3x+4y=96$. Draw the graph, find the pairs!
1d
suggested rejected edit on Matrix Derivative d(AXA)^(-1)/dX
1d
comment Is $a_i\mathbf e^i$ always equal to $a^i\mathbf e_i$?
Great point, well put +1.
2d
comment Resources on exterior algebra, wedge product, geometric product and tensors
Well that's ok, take the plunge. If you feel you may need further knowledge in Differential Geometry try John McCleary's Geometry from a Differentiable Viewpoint or Differential Geometry by Kreyszig.
2d
comment Resources on exterior algebra, wedge product, geometric product and tensors
I had working knowledge of Differential Geometry and Riemannian Geometry when I began self-studying the book in my first graduate year. I don't think you will see a huge jump; you may even try Nakahara's Geometry, Toplogy & Physics too - see amazon.co.uk/Geometry-Topology-Physics-Edition-Graduate/dp/…
2d
answered Resources on exterior algebra, wedge product, geometric product and tensors
Apr
21
answered Evaluating integrals with trigonometric function
Apr
21
comment Which type of correlation should I use?
I would say that the Pearson product moment gives you a very simple notion of correleation; basically a value close to $+1$ shows positivie correlation and $-1$ showing negative correlation. Spearman's shows dependence between variables.
Apr
21
comment What is the difference between CW-complex and Cellular complex?
@MTMA It is very easy to give a space the structure of a cell complex that is not also a CW complex structure. As an example, take one $0$-cell attach a $2$-cell to create the $2$-sphere then attach an additional $1$-cell to the interior of that $2$-cell. This gives a cell complex which is very easily checked to not be a CW-complex.
Apr
21
comment Formula for coefficient of Mahonian numbers
I think they are related to Hightower, Lassard and Tackleberry numbers.
Apr
21
comment What is the difference between CW-complex and Cellular complex?
My comment is fair - care to elaborate on the downvote? I'd like to improve this answer if possible.