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1d
comment How to solve this third degree polynomial?
Well - you might "spot" the fact that 320 factors as $5\times8^2$, and notice the factorisation $x^2(x-3)$ of the left-hand side, which then show that $x=8$ works :)
1d
comment Are there integrals you can't solve without inverse hyperbolic substitution?
You are welcome :)
1d
comment Are there integrals you can't solve without inverse hyperbolic substitution?
Well, since hyperbolic functions are really the same as trigonometric functions but just rotated by multiplication by $i$ in the complex plane, I would say no.
1d
answered Are there integrals you can't solve without inverse hyperbolic substitution?
Apr
14
answered Finding the equation of the tangent(s) from a point OFF the curve.
Apr
14
comment When is something “obvious”?
Agreed - and I believe I have been guilty of this myself on some rare occasions.
Apr
3
revised How to define the $0^0$?
edited body
Feb
5
comment Do we have $K(\beta)=K(\beta^2)$ for field extension of odd degree?
Yes $\;\;\;\;\;\;\;\;\;\;\;\;$
Jan
30
awarded  Generalist
Jan
28
answered Find bases for the subspaces $U_1, U_2, U_1 \cap U_2, U_1 + U_2$
Jan
27
comment Roots of Unity - Complex Numbers
@LoyalKnight It follows from De Moivre's theorem, as on this Wikipedia page, and it is one of the things that once you have used it a couple of times, it becomes a really useful fact to recall and use when needed.
Jan
27
answered Roots of Unity - Complex Numbers
Jan
25
comment Partitioning the naturals into an infinite number of large sets
I think we should just let them go, so long as they still sell us their whiskey!
Jan
25
reviewed Close how to find $ \lim\limits_{x \to \infty} \left(\sqrt{x^2 +1} +\sqrt{4x^2 + 1} - \sqrt{9x^2 + 1}\right)$
Jan
24
comment Cornacchia'sAlgorithm
@Sushma You can find me here on MO
Jan
24
reviewed Approve suggested edit on Difference between a “topology” and a “space”?
Jan
23
comment How come complex numbers represent coordinates?
Well, there is a very clear 1-1 correspondence between ordered pairs $(a,b)$ and numbers of the form $a+ib$.
Jan
23
comment Polynomial of degree 4 with real coefficients, two complex roots given.m
You can try posting some others, but remember always to explain what you have tried, or how far you have got, and exactly where you are stuck. I may not be online, but others will help.
Jan
23
revised Polynomial of degree 4 with real coefficients, two complex roots given.m
added 138 characters in body
Jan
23
answered Polynomial of degree 4 with real coefficients, two complex roots given.m