Mathematical Explanation of the Difference between SQL Joins: Inner ...
May 5, 2020 · Question What is a mathematically sound & intuitive explanation of all the inner and outer SQL joins that clearly shows the differences between them? Inner Join Left Join Right Join Full …
geometry - Writing SQL code to recognize when three input lengths …
May 29, 2018 · Writing SQL code to recognize when three input lengths form a triangle Ask Question Asked 7 years, 6 months ago Modified 4 years, 7 months ago
Is Cartesian Product same as SQL Full Outer Join?
Feb 8, 2014 · Is Cartesian Product same as Full Outer Join found in Relational Database SQL? I ask because I am taking a Discrete Mathematics course and I just want a better understanding of how …
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polyhedra - Polyhedron with least number of vertices whose diagonal ...
Dec 6, 2025 · We know in $\\mathbb{R}^2$ a polygon with the least number of vertices whose diagonals enclose an interior region is a pentagon. What about in $\\mathbb{R}^3$? The least number of …
Find the sum of the series $\\sum \\frac{1}{n(n+1)(n+2)}$
Mar 26, 2015 · I got this question in my maths paper Test the condition for convergence of $$\sum_ {n=1}^\infty \frac {1} {n (n+1) (n+2)}$$ and find the sum if it exists. I managed to show that the series …
Can I move the Lagrange multiplier to the other side?
Dec 6, 2025 · Like instead of saying $$\\nabla f=\\lambda\\nabla g$$ can I instead say $$\\lambda\\nabla f=\\nabla g$$ to create an easier system of equations to solve?
The mod97 operation in IBAN validation - Mathematics Stack Exchange
The international bank account number (IBAN) is validated by a $\bmod 97$ operation. Suppose an account number is like sd1234abcd78965h then the following steps are performed: the first four …
Give bases for col(A) and null(A) - Mathematics Stack Exchange
A small, but important omission: Those vectors are not $\operatorname {col} (A)$ and $\operatorname {null} (A)$. The vector spaces spanned by those vectors are. Alternatively: "A basis for …
Period of sum of sinusoids - Mathematics Stack Exchange
Beware that assuming there is a period to find is a big assumption. For example, suppose your two sinusoids are $\cos {2\pi t}$ and $\cos {\frac {2\pi t} {\sqrt {2}}}$. The periods of the two functions are …