In integration how much marks i will loose for not writing +c

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sachin_naik04
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1) in my exams there were 3 simple questions on integration carrying 5 marks each, i solved them correctly but the only mistake i did was at the end of each step i didnt write "+c"

like for example the final step of an integration problem is suppose say:
x2+9x2+c

so how much marks i will loose out of 5 for not writing that +c

2) and for another question i wrote √50 instead of writing 5√2 as the answer, is that ok or i will loose marks for the same, meaning can 5√2 be also written as √50
 
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oh thanks

but what about my second query i.e. can 5√2 be also written as √50, are both the things correct as far as an answer is concerned
 
sachin_naik04 said:
oh thanks

but what about my second query i.e. can 5√2 be also written as √50, are both the things correct as far as an answer is concerned

The more math a teacher knows, the less likely you are to get points off for this stuff. I could picture a middle school teacher taking points off for writing 3/2 instead of 1.5 or 1 1/2, or a high school algebra 1 teacher deducting points for your answer, but hopefully a calculus teacher will recognize that your answer is fine.

You'd have a valid complaint if any points are deducted.
 
Tobias Funke said:
The more math a teacher knows, the less likely you are to get points off for this stuff. I could picture a middle school teacher taking points off for writing 3/2 instead of 1.5 or 1 1/2, or a high school algebra 1 teacher deducting points for your answer, but hopefully a calculus teacher will recognize that your answer is fine.

You'd have a valid complaint if any points are deducted.

Agree. It's a calculus course, not a course in simplifying radicals.
 
HallsofIvy said:
Do you not understand that each teacher has to decide that for him or herself? No one can tell how many marks another person might take off for a specific mistake.

sachin_naik04 said:
oh thanks

but what about my second query i.e. can 5√2 be also written as √50, are both the things correct as far as an answer is concerned

HallsofIvy's response was directed at both questions. The same reasoning applies.

From my experience with forgetting +c is that you can hope to get 4/5. Depending on the teacher, either 1 point deducted for the first +c missing and then ignoring all others as "carry on" errors, or taking 1/2 off for each question. You can argue for more points if the teacher chooses this second approach. Something along the lines of "Of course, if I put +c in anyone of them, I would've remembered to do that for all of them".
 
Great. Will this site become a place to get ammunition to argue for partial credit with your instructor?
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X^2 + 9x^2 = 10x^2
 
Long answer:*
I think the simplification is more a matter of taste.
Personally, I would say that √50 is at least just as good as 5√2 and would not deduct points for that, just like for writing ln(1/2). However, this is a thin line: when a student wrote down √49 or ln(1/e) I would definitely not give them full credit.

In integration problems, also the context of the problem plays a part. Does the question ask for the or a primitive function? Is the integration the end goal of the exercise, or part of a larger question? Are there integration boundaries (like in: calculate the area under the graph)?


*) Short answer: What Halls said[/size]
 
I'd say that it depends on the problem.. If it was a more theoretical problem, the + C part has enough significance to lose some marks.. If it was more computational, I wouldn't deduct too many marks -- you did to most of the work. But anyway, I once lost enough marks for forgetting a '=' sign in a '<=' sign.. And I think that forgetting + C is worse.
 
If the limits aren't there, you should add the plus C...
 
not lost a single mark

wow i have not lost a single mark for not writing that +c i got exactly 70 marks as i wanted, can't believe

just reveled from the stress