If you can only do the 2nd part...?? (1 Viewer)

kpq_sniper017

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If there was a question in which (i) required a proof and (ii) required an application of the proof, can you get full marks for (ii) without having first done (i):

e.g.
(i) Prove cos2A = 1 - 2sin<sup>2</sup>A
(ii) Hence, find the indefinite integral of cos2A.

I know that's a stupid question in practise (it's the first example I thought of), but if you didn't know how to do the proof in (i), could you still get full marks for (ii) - of course, this is provided the examiner's state: Prove LHS=RHS and don't just tell you to find a result and use it without telling you the result first.
 

dawso

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yeah u do, thats why they do that shit, if u cant get the first one, u can use the result to do the second part, thats in the hsc neway
 

Xayma

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Yes each part of the question is in effect a seperate section ie you can only be marked on what you have in that section and it doesnt ask for a proof in that section just to use it.
 

CM_Tutor

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However, in the question structure you have described, you would need to use the result from (i) to get the marks for (ii). That is, if you said "I can't do (i), but I can do (ii) without (i), by some other method", you wouldn't get full marks for (ii), because of the 'hence'.
 

iambored

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what if you 'pretended' to do i (write something random and make the answer 20), and got an answer. then you used the answer for ii, can you get full marks for it? because of the marking style, where they will not take marks off for the 2nd part if you use your results from the first part?
 

Xayma

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If you did that for something like *Find the interest at this bank
and then *How much money will Fred have after investing $1 for 15yrs.

Then Im pretty sure they will mark your answer with the interest found in the other part.

But I think there is limits, ie if you put 0% then they wouldnt mark it correct (I think) especially if it is superannuation or something
 
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