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rinny
01-12-2005, 07:54 PM
i saw someone else post their math question, so i have a question regarding transformations and sin waves if anyone remembers it...

question on paper: Use a sin regression to find the equation, in the form f(n)= a sin[b(n-c)] +d...State values of a, b, c, and d

now, when i graph a sin regression, it automatically gives me values ABCD (2.334, 0.016, 1.812, 6.528)

BUT

the values i originally receive are entered into a formula in the form f(n)=a sin (bn-c) +d which is not the same as the form "f(n)= a sin[b(n-c)] + d" that the question asks for because in the form f(n)= a sin[b(n-c)] + d B is OUTSIDE of the brackets and c would also be changed since when you take B outside of the brackets you use lowest common denominator and C is changed...

SO

can anyone tell me what B and C would be in this form f(n)= a sin[b(n-c)] + d ?? im thinking B would be 0.016 and c would be 113.25 so it would look like 2.334 sin[.016 (n+113.25) ] + 6.528 because if u were to distribute B back into the brackets then it would be 0.016n-1.1812???

rinny
01-12-2005, 08:06 PM
nevermind, i got it, that is the right answer...this post can be closed/deleted whatever

Neil4Speed
01-12-2005, 08:07 PM
... hmm those numbers look a little familiar... Looking for some help with the diploma project I see lol.

Best of Luck

rinny
01-13-2005, 12:14 AM
haha, exactly...do u have answers for Part A #6, PART B #'s 4b and 6 by chance?? or some guidance on them?

SmAcKpOo
01-13-2005, 11:03 PM
wow i took the course last semester and i already forget that crap.

elmo909
01-14-2005, 12:42 AM
Originally posted by SmAcKpOo
wow i took the course last semester and i already forget that crap.
I forget most of the stuff in most of my courses. I'm just wondering if this is going to haunt me in my first year university in engg :eek:

H4LFY2nR
01-15-2005, 09:33 AM
Originally posted by elmo909

I forget most of the stuff in most of my courses. I'm just wondering if this is going to haunt me in my first year university in engg :eek:
No not really. Remember as much calculus as possible though, pretty much every course uses it.

elmo909
01-15-2005, 06:38 PM
Originally posted by H4LFY2nR

No not really. Remember as much calculus as possible though, pretty much every course uses it.
I don't think I can ever forget calculus. I don't have the highest mark, its >80%, but I think I understand what is going any way better than these people with >90% averages, sometimes I think they just memorize how to do the math and dont know whats going on. I get that impression from talking to them about math.