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 17h asked Generalisation of Cramer's rule to matrices Apr 29 awarded Nice Question Apr 26 comment Anti-Derivative of $\ln(x^2 + 7)$ is kicking my butt, can anyone help? Investigate $\int \ln x$ first. Apr 18 comment Are all numbers expressible as a complex number? Not sure what you mean exactly, but there are the Quarternions $\mathbb{H}$ and the Octonions $\mathbb{O}$. Apr 8 revised Can a change of variable result in the evaluation of an integral in terms of elementary functions, whereas before the c.o.v. this was not possible? spelling mistake Apr 8 revised Integration demonstration on my Calculus exam Updated Latex - please check this still states what you originally meant. Apr 3 comment Minimising the length of the vector $r(t) = \sqrt{2}\sin{t}\mathbf{i}+\cos{2t}\mathbf{j}$ for $t \in (0, \pi/2)$ Differentiate the magnitude, set to zero and solve. Second derivative may be required to decide min/max. Mar 31 comment Finding $\int \frac{e^x\left(-2x^2+12x-20\right)}{x^3-6x^2+12x-8}dx$ Partial fractions is the way to go. Yes it involves the $Ei(x)$ function, but the total sum of these terms cancels to zero, leaving the single term you require. Mar 31 comment Finding $\int \frac{e^x\left(-2x^2+12x-20\right)}{x^3-6x^2+12x-8}dx$ Maybe partial fractions? Or can the numerator be factorised? Mar 29 comment Why are mathematicians so interested in finding out the gaps between primes and the distribution (randomness) in primes? For interest/fun: the $n$-th prime number $p_n\sim n\log n$. Mar 27 answered What books should I get to self study beyond Calculus for someone about to start undergrad mathematics? Mar 25 comment Comparing infinite values In that case you don't deserve a downvote! Mar 25 comment Comparing infinite values This is not the whole expression under investigation (ps I did not downvote) Mar 21 revised Can a change of variable result in the evaluation of an integral in terms of elementary functions, whereas before the c.o.v. this was not possible? added 599 characters in body Mar 20 accepted Can a change of variable result in the evaluation of an integral in terms of elementary functions, whereas before the c.o.v. this was not possible? Mar 20 comment Can a change of variable result in the evaluation of an integral in terms of elementary functions, whereas before the c.o.v. this was not possible? To clarify, the integral $I$, i.e. the primitive $F$ of $f$, is not elementary in the question. Mar 20 revised Can a change of variable result in the evaluation of an integral in terms of elementary functions, whereas before the c.o.v. this was not possible? added 4 characters in body Mar 20 asked Can a change of variable result in the evaluation of an integral in terms of elementary functions, whereas before the c.o.v. this was not possible? Mar 18 revised I need to solve $\phi (x,y) = \frac{2V}{\pi} \int_{0}^{\infty} \frac{\sin(kx)\cosh(ky) dk}{k\cosh(ka)}$ added 156 characters in body Mar 16 comment Find a succinct problem whose solution requires methods from many sub-branches of mathematics Check out this, particularly near the end. There are mentions of the different areas of Mathematics used in Wiles' proof: vimeo.com/18216532