maths question - trial and improvement

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sqrt of 5
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i got x = 2.8 to 1 d.p is that correct?
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ghostwalker
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(Original post by sqrt of 5)
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i got x = 2.8 to 1 d.p is that correct?
No, actual root is 2.8686...
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sqrt of 5
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(Original post by ghostwalker)
No, actual root is 2.8686...
????????????? the answer must be to 1 dp
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ghostwalker
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(Original post by sqrt of 5)
????????????? the answer must be to 1 dp
So, correct to 1 dec.pl. it's 2.9
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sqrt of 5
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(Original post by ghostwalker)
So, correct to 1 dec.pl. it's 2.9
it's wrong according to mathswatch
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sqrt of 5
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I give up i spent a whole evening -.-"
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ghostwalker
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(Original post by sqrt of 5)
it's wrong according to mathswatch
Which is wrong?
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sqrt of 5
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(Original post by ghostwalker)
Which is wrong?
2.9 or the other value you gave to me
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ghostwalker
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(Original post by sqrt of 5)
2.9 or the other value you gave to me
If you want the root as far as the first decimal place, it's 2.8

If you want it correct to 1 dec.pl. it's 2.9, as that is closer to the actual root than 2.8.

Going to depend on the exact wording of the question.

I'd interpret it as the latter, 2.9
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sqrt of 5
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(Original post by ghostwalker)
If you want the root as far as the first decimal place, it's 2.8

If you want it correct to 1 dec.pl. it's 2.9, as that is closer to the actual root than 2.8.

Going to depend on the exact wording of the question.

I'd interpret it as the latter, 2.9
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!!
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Notnek
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!!
You haven't written any working.

Tagging in Muttley79 who knows more about the bizarre mysteries of MathsWatch so can help if you have further problems
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sqrt of 5
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(Original post by Notnek)
You haven't written any working.

Tagging in Muttley79 who knows more about the bizarre mysteries of MathsWatch so can help better
it doesn't matter, it should give a mark for the right answer. Thank you!
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Notnek
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(Original post by sqrt of 5)
it doesn't matter, it should give a mark for the right answer
It says "you must show all your working" so I'd try putting in working and see what happens.
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sqrt of 5
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(Original post by ghostwalker)
2.9 to 1 decimal place means the root is in the inteval 2.9\pm 0.05, which it is.

Mathswatch is incorrect.
how did you get 2.9 to 1dp? can you show your working out so I can type it into the box?
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Muttley79
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(Original post by sqrt of 5)
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You need to show working - try x = 2, then x = 3 then 2.5 by substituting in that will tell you whether the root is between 2 and 2.5 or 2.5 and 3. post what you get ...
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Notnek
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(Original post by sqrt of 5)
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i got x = 2.8 to 1 d.p is that correct?
Is this a GCSE question out of interest?
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ghostwalker
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(Original post by sqrt of 5)
how did you get 2.9 to 1dp? can you show your working out so I can type it into the box?
No, I've no idea what sort of working Mathswatch wants.

If you're not getting 2.9, I suggest posting your working.
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(Original post by Notnek)
Is this a GCSE question out of interest?
yep

(Original post by ghostwalker)
No, I've no idea what sort of working Mathswatch wants.

If you're not getting 2.9, I suggest posting your working.
im trying ill tell you in a bit
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Notnek
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(Original post by sqrt of 5)
yep
Trial and improvement isn't part of GCSE maths anymore. Were you set this work? If not then there's probably no point doing it.
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(Original post by Notnek)
Trial and improvement isn't part of GCSE maths anymore. Were you set this work? If not then there's probably no point doing it.
:OOOOOOO are you serious? à_à you might be right! the spec only says iterative methods

(Original post by ghostwalker)
No, I've no idea what sort of working Mathswatch wants.

If you're not getting 2.9, I suggest posting your working.
ok now it does work è_é


Notnek ghostwalker Muttley79 I don't wanna open a new post, can you please give me some hints (not the answer) for this question?

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