Help on Problem 15 Chapter 1 of Hungerford's Algebra
6755
A finite, cancellative semigroup is a group
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A proof for Atiyah-Macdonald Exercise I.21.iii
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$\chi(G)+\chi(G')\leq n+1$
91684
Prove the following equation(much needed help):
148139
Exercise $1.8$ of chapter one in Hartshorne.
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Find $P(n+1)$ for a polynomial P
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Determining the parity of the coefficients of a quadratic given that there is a rational solution
126445
Proving the second root of a quadratic equation
139540
Real Analysis, Folland Problem 1.3.15 Measures
53713
Accumulation Points for $S = \{(-1)^n + \frac1n \mid n \in \mathbb{N}\}$
107765
Prove that there exists two roots in $[-1,1]$
154945
$|px^2+qx+r|\le1$ for all $x$ in $[-1; 1]$, show that $|rx^2+qx+p|\le2$ for all $x$ in $[-1; 1]$
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Not sure how to go about this group theory proof
16548
Prove $(x+y) \text{ mod } n = ((x \text{ mod } n)+(y \text{ mod } n)) \text{ mod } n,\,$ and product analog
116856
Proving that a polynomial of the form $(x-a_1)\cdots(x-a_n) + 1$ is irreducible over $\mathbb{Q}$
107435
Exercise from Atiyah-Macdonald, Chapter 1, 2.iv)
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How to solve this set of symmetric polynomial expressions