Recent content by Bazman

Hi There, HallsofIvy thanks for your help with this. I got to couple of quesitons see your amended quote and below. even given the last couple of points surely I am still stuck with one equation and two unknowns? u AND x. u^3- (1.45+ x^2)u+ 1.44x= 0

I mean corelation between two random variables so the correlation matrix shouls be symmetric and positive defintie. So the x in the equation represents the unknown correlation between A and C. Well this is the problem: look at the equation circa half way down...

the correlation between A and B is 0.8 and between B and C is 0.9. I have to calculate what the least correlation A and C can be. \begin{pmatrix} 1 & 0.8 & x\\ 0.8 & 1 & 0.9\\ x & 0.9 & 1 \end{pmatrix} using sthe standard equation for eigenvalues you get...

ah got it! Thanks Pizzasky

Hi, The final answer below is wrong. Is should be 8a! Not sure where I made the error below? Also is there another substitution that can be used at the earlier line a \int_0^{2 \pi} \{ 2( 1 - \sin \phi) \}^{\frac{1}{2}} d\phi to subtitute for the (1 - \sin \phi) without the need...

Hi VietDao, I managed to figure it out. Your hint brought me a lot closer to the solution than I initially realized! Thanks again :smile:

Hey VietDao29! Thanks for your help on this. I assume that the rest of the answer rely's on my using the reduction formula for trigonometric integrals? I've had a quick scoot on the web and there seems to be two main cases m+n odd or m+n even. Which uses two different formula (which...

Hi, J(m,n) = \int_0^{\frac{\pi}{2}} \cos^m \theta \sin^n \theta d\theta First of all I had to evaluate the following ( I don't know what the correct answers are but here are my calculations: J(0,0) = [\theta]_0^{\frac{{\pi}{2}}}=\frac{\pi}{2} J(0,1) = [-\cos...

thanks Murshid! Its crystal clear now

Hi, I need to prove the following: 1+ \frac{ 1}{ 2!} + \frac{1 }{3!} +...+ \frac{ 1}{ n!} < 2 \lbrack 1 - ( \frac{ 1}{2 } )^n \rbrack From trying various example I'm fairly sure the relation holds but I can't seem to prove it algebraically? Does the ineqaulity make a...

OK will do is there a guide to using Latec on this Forum?

Hi, I have to find the total number of permutations of four letters that can be selected form the word "ARRANGEMENT". Clearly we have 7 different letters so the amount of 4 letter permutations with no repeats is: 7!/3!=840 now for each two letter can form a four letter permutaion...

Hi, To solve the following d.e.: xdy-ydx = 0 1 you get ln(y)-ln(x)=C 2 no clearly you can simplify to: ln(y/x)=c 3 which after taking exponentials gives: y=Ax where A=e^c 4 however what interests me is if you do not simplify...

Hi, i've seen a textbook where the integration inthe following expression is performed: C(S,V,t) = 1-(1/2pi)*exp[-lambda(k0)*t](u(k0,V)/k0^2-i*k0) + infin *S exp[-.5*kr^2*lambda''(k0)*t]dkr - infin where kr is k subscript r and k0 is ksubscript 0 i = complex number lamda''...

Sorry problem 1 above should read 1.) x^y*|ln(1/x)|^m behave for any m given y<1 as x-> infinity but I don;t think that changes the nature of your argument. In any case thanks will look into L'hopital's rule