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Dec
21
comment Find $n$ if the area between the curve of $y=x^n$ and the $y$ axis is $3$ times the area between the curve and the $x$-axis
@luluja yes, see last equation, it is only in terms of $B$
Dec
21
comment Find $n$ if the area between the curve of $y=x^n$ and the $y$ axis is $3$ times the area between the curve and the $x$-axis
@luluja not sure which part doesn't work -- what exactly doesn't work?
Dec
21
comment Is it valid to calculate standard deviation for n=2?
@YvesDaoust i took it to be the size of the entire population, not the size of the sample from it...
Dec
21
comment Are $\Bbb C^4 $and polynomials of degree at most five isomorphic vector spaces?
@Lubin he is talking about the set of all functions with 4 continuous derivatives
Dec
21
comment Is it valid to calculate standard deviation for n=2?
@YvesDaoust OP was discussing std dev, not its estimation from a sample...
Dec
21
comment Nearly every $x^2+y^2=z^2$ has two more solutions $x_2^2+y_2^2=z^2$ and $x_3^2+y_3^2=z^2$ is this known?
can you illustrate with $3^2+4^2=5^2$?
Dec
21
comment Is it valid to calculate standard deviation for n=2?
@YvesDaoust the first one was my intuition too - no indeterminacy: $$\sigma^2 = \frac{1}{n} \sum_{k = 1}^n (x_k - \mu)^2 = \frac{(x_1 - \mu)^2}{1} = 0$$ since $x_1 = \mu$...
Dec
21
comment Is it valid to calculate standard deviation for n=2?
@YvesDaoust interesting -- why? If you the entire population of 1 element, its distance from itself is certainly 0...
Dec
21
comment what is the complement of empty language?
why woould you think there is smtth wrong?
Dec
21
comment comparing probability of different size
@jonnyLee you are talking about the confidence interval of being corect for an item of each type
Dec
18
comment Calculate the determinant of the matrices $a_{ij}=\frac{1}{i+j-1}$ and $b_{ij}=\frac{1}{i+j}$?
Indices start from 1 or from 0?
Dec
18
comment Calculus contradiction?
does not answer OP's question - he asked why they are different, when they are supposed to be the same. You answered how to arrive at those answers...
Dec
18
comment Limit involving exponentials of $\arcsin(x)$ and $\arctan(x)$
@user26977 he said no Taylor series
Dec
18
comment Mean of the deviations from the mean
@ronn you have $n+1$ values, count them: $y+0a, y+1a, \ldots, y+na$...
Dec
18
comment Integrate $4x/(x^4-1)$ dx
@Dr.MV fixed, thanks
Dec
16
comment What is the name of the theorem?
@AyleanClaraGrandieur see update with full text & hyperlink
Dec
15
comment Integral of the product of a power function and an arbitrary exponentiated function
not sure it helps but substituting $u = t^a$ yields $$\frac{1}{a} \int \exp\left( \frac{u^{1/a} \ln 2}{\lambda} - \frac{u}{b}\right) du$$
Dec
15
comment Probability - Limits of integration for Z=X+Y, with bivariate density f(x,y)
you should have $$f_Z(z) = \int_\mathbb{R} f(x,z-x) dx$$
Dec
15
comment Extending relation to be transitive
Say, it is transitive and you are using the matrix representation. Pick some $a \sim b$ and $b \sim c$ and mark them in your matrix. What entry does $a \sim c$ represent? can you generalize this?
Dec
15
comment System of differential equation
@Ergo your approach isn't always correct. E.g. here, it won't work. Definition of $e^{tA}$ (it is also a matrix) is from the Taylor series in the answer. You can simplifyit greatly by just computing $A^2$. What do you get? Then multiply by $\vec{F}(0)$ on the right to get the answer...