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February 25th, 2010, 04:19 AM   #1
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I collected questions from different papers and I tried to s

Hi

I collected questions from different papers and I tried to solve them by myself and I want to correct them
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February 25th, 2010, 05:59 AM   #2
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Re: I collected questions from different papers and I tried to s

#2. The way I see it...

Be careful how you write your statements. Be complete ...don't try to hurry and miss steps.

Write things like L.S. = ...and complete that. Then R.S. = and complete that by rearranging to take the form needed.

You have ...+ (2k - 1)^2 + (2k + 1 - 1)^2, but then correct that to + (2k - 1)^2 + ((2k + 1) - 1)^2, and follow that with an error in (2k + k - 1)^2

With such errors you still finally seem to wind up with the correct result, but were not quite clear on how you did the rearranging to get what you want, and in fact should not have obtained a correct result from the above errors ...so you are trying to force the result, rather than make sure of clear, logical steps.

All I'm saying is to pay attention to the small details and the rest will follow. You have the right general idea, just take your time, and remember that you are writing something for someone else to read. So don't miss out any words, or they [and you] will get confused. Just be careful and you'll fare a lot better in the long run.

#3. Again, slowdown and write clear statements. Do you mean...

S(1) = 3(1) + 3 = 6
S(2) = 3(2) + 3 = 9
So d = 9 - 6 = 3

Write clearly. Is that a "sigma" before the 6 and the 9? It shouldn't be there!
Don't miss off = signs etc. You are writing for someone else to read. Make it easy for them. Also you lessen y far your own chances of making an error. Allow for loss of marks for lack of knowledge, not for silly mistakes which can so occur.

The arithmetic seems OK, but look before you leap. The 2 would divide nicely into the even result of the square brackets, so don't divide it first into the odd number 51. Just little time-savers all of which add up along the way at exam time.

Part b) is difficult to read. Your substitution is incorrect: t(6) = 625(r^(6-1)) = 625r^5 = -32/5 etc.
Also, -6.4/625 is not exactly -0.01. For future reference...stick to fractions [and learn if you are not sure on that ...it IS important] rather than try to work everything in decimals.

You might try that one again. I've also been known to make mistakes , so please also check my work while you are at it. Good luck.
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