2,648 reputation
421
bio website
location
age
visits member for 2 years, 10 months
seen 3 hours ago

Apr
16
revised How do you evaluate $f(x_n)$?
edited body
Apr
16
answered How do you evaluate $f(x_n)$?
Apr
15
comment Proof by contradiction and order of statements
@Amateur yep. I take it back.
Apr
15
comment Proof by contradiction and order of statements
@Amateur I'm not sure that it's correct to say that $\mathbb{R}$ is a closed interval, although you're certainly right that it's a closed set.
Apr
15
comment Proof by contradiction and order of statements
For your last note, just make a truth table and check.
Apr
15
comment applications of derivatives : maxima and minima
Do you have any thoughts on this? What would it mean if the derivative of a function at a point was $10100$? What would the function look like at that point? Why couldn't that be a maximum?
Apr
15
comment Problem with trigonometric equation
That problem looks pretty tough to solve analytically to me. Where did you come across it?
Apr
15
comment Question about the Continuum Hypothesis
The answer to "where did I go wrong" is that OP took "Clearly this is either true or false - there either exists such a set, or there does not exist such a set" to be true, and this demonstrates that that's not so obvious.
Apr
15
answered Question about the Continuum Hypothesis
Apr
14
reviewed Approve suggested edit on Autocorrelation and spectral density in MATLAB
Apr
14
comment If $x^2 +xy =10$ then when $x=2$ what is $\frac{dy}{dx}$?
do you mean "when $x=2$"?
Apr
14
answered Let $n\ge 2$ be an integer. If $\gcd(a,b^n)=1$, then $\gcd(a,b)=1$
Apr
14
reviewed Approve suggested edit on Linear Algebra nullSpace and multiplication
Apr
14
comment Probability Equation That I am missing here
"Don't ask me why but I just logically see that it is 50% so why?" That's a dangerous way to think about math.
Apr
13
answered Every n × n-matrix A with real entries has at least one real eigenvalue.
Apr
13
comment Writing Series as a Telescoping Series
yes, I was mistaken, sorry :(. I realized immediately and deleted my comment.
Apr
13
comment Proof by induction valid or not?
@DavidK I know. But either way, it is never correct to assume that the formula works for all $n$.
Apr
13
comment Writing Series as a Telescoping Series
That's not $S_N$. It's $t_N$ where $S_N=\sum_{i=9}^N t_N$.
Apr
13
answered Writing Series as a Telescoping Series
Apr
13
reviewed Approve suggested edit on Limited completeness and restricted quantifiers