Recent content by bubokribuck

Hi sunjin09, thanks for your reply, but there are two variables x and y involved though, how can I convert (x,y) into (t) please?

Hi, I have problems rewriting equations with the term y'' as a system of first order differential equations. I've been given several equations and was told to write them as 1st order DEs, then calculate the numerical solution using the Euler's modified method. I know that y'=f(x,y), so if...

Can't do this question :( please someone help I have managed to do part(A) and the answer I've got is 22 (when S=200). However, I'm stuck at part(B) at the moment. Here's what I've done so far for (B).I don't know how to work out the values of S for which a square cannot be constructed. Any...

Hum... I'm not quite sure how to do that, the furthest I can go is: (-1)^{n+1} - 1 = (-1)^n(-1)^1 - 1 = -(-1)^n - 1 But the problem is when n=1, the denominator is still equal to zero (which is obviously wrong).

Yes, I know that if 1) a and b are parallel, axb=0 2) a and b are perpendicular, axb=|a||b|n But in the past I have been given specific vectors like a=(1,2,3) b=(5,3,2). This time, I've only been given statements such as "orthogonal to z-axix", and I really don't have a clue what that actually...

(1) Let f(x)=x^3+y^3+z^3-3xyz, Find grad(f). grad(f)=(3x^2-3yz, 3y^2-3xz, 3z^2-3xy). (2) Identify the points at which grad(f) is a) orthogonal to the z-axis b) parallel to the x-axis c) zero.I have managed to solve for (1), but don't have a clue how to solve for the second part. I have not...

Hi spamiam, I don't seem to be able to cancel out the terms, is there something I've done wrong?

Hi, the doc exceeds the upload size limit, therefore I can only upload png. Thanks :)

Hi, the calculations are quite long, so I've attached a document. :)

Hi spamiam, here's what I've got for the Fourier series: And here's the sigma equation I've come up with for the last part of the question.

Ah, I think I am getting it now! Let N denotes the numerator, and D denotes the denominator, then D=(2N-1)(2N+1). Is this right? So for the nth term, it would be something like (-1)n+1\frac{2n-1}{(4n-3)(4n-1)}

If the first term is n=1, then the numerator of the first term would be 2n-1 right? (as 2(1)-1=1)

Hi Joffan, here it is.

Hi spamiam, here's the full question, but I don't like it has anything to do with the previous parts though.

Yes I have noticed the alternating signs, but couldn't find any relationship between the numerator and the denominator though :(