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1. maths writing equations properly - the wording of things
Can't figure out whats wrong with these statements please see attatched

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2. Re: maths writing equations properly - the wording of things
(Original post by CasualSoul)
Can't figure out whats wrong with these statements please see attatched

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In point 3 you have just mentioned f(x), you need to mention that you will find roots of f(x)=0.
3. Re: maths writing equations properly - the wording of things
(Original post by CasualSoul)
Can't figure out whats wrong with these statements please see attatched
3) Quite simply:

is an equality. It is true for all within the domain of . There is nothing to be solved.

or is an equation. It is true for specific values of (i.e. roots which are found by solving the equation)

9) Not familiar with this, sorry.

10) I do not understand what is being rearranged, could you expand?
4. Re: maths writing equations properly - the wording of things
(Original post by CasualSoul)
Can't figure out whats wrong with these statements please see attatched

'
9 is wrong because x=0.3+/-).1 means x=0.4 or 0.2. However x should be bounded between those limits. It would be better to say 0.2<x<0.4.

10 iI think 10 is wrong because "my rearrangement should work" sounds vague. Would be better to say "the rearrangement is valid". Or maybe it's because a rearrangment should always hold true and would not depend on g'.
Last edited by Blutooth; 11-06-2012 at 10:45.
5. Re: maths writing equations properly - the wording of things
(Original post by Lord of the Flies)
3) Quite simply:

is an equality. It is true for all within the domain of . There is nothing to be solved.

or is an equation. It is true for specific values of (i.e. roots which are found by solving the equation)

9) Not familiar with this, sorry.

10) I do not understand what is being rearranged, could you expand?
Errm I' m not too sure what's being arrangeed..we were jsut given these statements and told to ensure we don't include statements like this in our coursework ..we should be able to figure out whats wrong with them without further info
6. Re: maths writing equations properly - the wording of things
(Original post by Blutooth)
9 is wrong because x=0.3+/-).1 means x=0.4 or 0.2. However x should be bounded between those limits. It would be better to say 0.2<x<0.4.

10 iI think 10 is wrong because "my rearrangement should work" sounds vague. Would be better to say "the rearrangement is valid". Or maybe it's because a rearrangment should always hold true and would not depend on g'.
Thanks !

hmm..I think the problem may lie with the g'<1 .....g' means g differentiated ..so maybe it' something to do with the notion of that ..arghhh I have noo idea
7. Re: maths writing equations properly - the wording of things
(Original post by CasualSoul)
Thanks !

hmm..I think the problem may lie with the g'<1 .....g' means g differentiated ..so maybe it' something to do with the notion of that ..arghhh I have noo idea
y' is an accepted notation. Perhaps it would be better if it was said y'<1 for all values of x of for x=1 or whatever
8. Re: maths writing equations properly - the wording of things
(Original post by Blutooth)
y' is an accepted notation. Perhaps it would be better if it was said y'<1 for all values of x of for x=1 or whatever
I think you're right you know . So t should say something a long the lines of g' (x)<1 or w/e variable the equation is in

9. Re: maths writing equations properly - the wording of things
(Original post by CasualSoul)
I think you're right you know . So t should say something a long the lines of g' (x)<1 or w/e variable the equation is in

TBH g' or g'(x) should both be fine. I'd probably go for g'(x) though. The important thing is that you still need to say the values of x (assumming g is a function in x) for which this holds. I also till think that a "rearrangment" should always hold true since it is just a rearrangement of some equation- but it's hard to know without seeing the question.
Last edited by Blutooth; 11-06-2012 at 13:09.