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Turn decimals to exact form

DjcrissYT

2.8284271247461901 to square root please

Reply 1

Lemur14

Volunteer Section Leader

Original post by DjcrissYT

2.8284271247461901 to square root please

Have you been taught a method for this?
My first thought for a number with that many decimal places would be trial and error. You know it's between 4 and 9 (since

\sqrt{4} = \pm{2} \text{and} \sqrt{9} = \pm{3}

) so start by trying the integers then if necessary get more precise :smile:

Reply 2

username1732133

Original post by DjcrissYT

2.8284271247461901 to square root please

That decimal is in its exact form. It is what it is.

It happens to be close to

\sqrt{8}

which you can check by squaring it.

What was the exact wording of the question?

Reply 3

Lemur14

Volunteer Section Leader

Original post by BuryMathsTutor

That's a much better way of doing it :facepalm:

Thought I was missing something...
In future though it's best not to provide full solutions, but instead to say if you square it then it will find the number to go under the square root :smile:

Thanks!

Reply 4

username1732133

Original post by Lemur14

...but instead to say if you square it then it will find the number to go under the square root :smile:

Thanks!

Wouldn't that also amount to giving the solution? :biggrin:

Reply 5

Lemur14

Volunteer Section Leader

Original post by BuryMathsTutor

Wouldn't that also amount to giving the solution? :biggrin:

Requires them to get their calculator out at least! Could be argued either way, I'd say no, but I'm sure plenty of others would disagree.

Reply 6

Notnek

I think the OP needs to post the full question.

Reply 7

Notnek

Original post by Lemur14

Requires them to get their calculator out at least! Could be argued either way, I'd say no, but I'm sure plenty of others would disagree.

I think it's irrelevant if either of you posted full solutions because the question as it was posted needs more context (it's a strange question otherwise), plus there's a good chance that the OP won't come back :smile:

Reply 8

Lemur14

Volunteer Section Leader