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ys wong
  • Member for 8 years, 2 months
  • Last seen more than 3 years ago
1 answer
14 votes
4k views
5 bookmarks
My first proof that uses the well-ordering principle (very simple number theory). Please mark/grade.
2 answers
3 votes
124 views
3 bookmarks
Show $f$ is not $1-1$
4 answers
3 votes
3k views
2 bookmarks
Proving whether the difference of two series is convergent of divergent
3 answers
3 votes
108 views
1 bookmarks
Evaluate the following complex integrals using parameterisation $\int \limits_{\beta} f(z) dz$
1 answer
3 votes
252 views
1 bookmarks
Fundamental Theorem of Algebra proof, for max real roots of real polynomials - using only high school algebra-precalc?
0 answers
2 votes
340 views
1 bookmarks
Showing that the equation $f(x)=1$ satisfy the condition of the fourier integral
3 answers
2 votes
1k views
1 bookmarks
Prove/Disprove that the set of rational numbers is uncountable (Real Analysis)
0 answers
2 votes
807 views
2 bookmarks
Solve the Neumann problem for the wave equation on the half line $-\infty < x <0 $.
1 answer
1 vote
354 views
2 bookmarks
Modelling a Forced undamped oscillation via ODE
0 answers
1 vote
84 views
2 bookmarks
Solving a wave equation (PDE)
1 answer
1 vote
105 views
1 bookmarks
Proving the existence and uniqueness of a cyclic group of $G$ (Group Theory)
2 answers
1 vote
109 views
1 bookmarks
Every subgroup $H$ of $G$ with $H\ne G$ is cyclic. Is $G$ cyclic?
1 answer
1 vote
287 views
1 bookmarks
Prove that it is impossible that every non-identity element of $G$ has an order of $2$.
1 answer
1 vote
3k views
1 bookmarks
Solving a first order linear ODE and determining the behavior of its solutions
1 answer
1 vote
573 views
1 bookmarks
Finding two complex conjugate roots from a cubic equation
1 answer
1 vote
155 views
1 bookmarks
Finding the coordinates of point $R$ in a parallelogram
1 answer
0 votes
1k views
1 bookmarks
Inspecting Direction field
1 answer
0 votes
6k views
1 bookmarks
Residues of $f(z)=\frac{z^2-2z}{(z+1)^2(z^2+4)}$
1 answer
0 votes
67 views
1 bookmarks
Using the Properties of Similar triangles and angle properties to find the length AC
1 answer
0 votes
47 views
1 bookmarks
Calculate angle DPA (Congruent and Similar triangles)
1 answer
0 votes
71 views
1 bookmarks
Show that angle BOC is $0.691$ radians
1 answer
0 votes
88 views
1 bookmarks
Finding Angle BDF inside a circle
2 answers
0 votes
90 views
2 bookmarks
If the radius of the smallest circle is x cm form an equation in x and show that it reduces to a quadratic equation