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bigbirdbanana

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Ok this is gonna sound weird but i got 4 answers for that, one of which was 9, because a square root can be positive or negative. So i had 10 - 1 = 9, 10 - -1 = 11, -10 - 1 = -9, -10 - -1 = -11

I found it weird that they seemed to only ask for one solution, unless there was another parameter to the question that i missed?
 

bigbirdbanana

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Well it can't equal 0, because whilst all the other roots cancel out, -sqr1 and sqr100 don't, so the answer must come from adding these two. I'm just wondering about the issue of the square roots being able to be positive or negative :S hopefully they understand what I mean by that so I don't lose marks there, because I originally just had 9.
 

barbernator

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Ok this is gonna sound weird but i got 4 answers for that, one of which was 9, because a square root can be positive or negative. So i had 10 - 1 = 9, 10 - -1 = 11, -10 - 1 = -9, -10 - -1 = -11

I found it weird that they seemed to only ask for one solution, unless there was another parameter to the question that i missed?
Square roots are only positive or negative if stated, or when you evaluate them from taking the square root of a square. if there is a number, e.g. sqrt 100, it is only equal to 10, NOT -10
 

Neologism

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Okay guys, so I got this question out, showed ALL working, even wrote the line '-1+10' but then underneathe I wrote '11' which I know is COMPLETELY STUPID especially since I do 3U! But seriously, will they still give me the mark or take it away for doing something that stupid ahhhh I was freaking at the end of the exam :( How much was it worth? 1 or 2?
 

weirdguy99

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Okay guys, so I got this question out, showed ALL working, even wrote the line '-1+10' but then underneathe I wrote '11' which I know is COMPLETELY STUPID especially since I do 3U! But seriously, will they still give me the mark or take it away for doing something that stupid ahhhh I was freaking at the end of the exam :( How much was it worth? 1 or 2?
It's a two marker, but I would personally give you 2/2 since well, you got everything right up until the end..
 

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