That homework help thread.

[Hannah]

Pretty self-explanatory, eh? Oodles of smart people who are all smart in different areas means one thing; a kick ass homework help forum. So, have at it.

[Hannah]

O.o Unless your math program encourages negative exponents, it looks pretty simplified to me...

A decimal number will not be exact though because irrational numbers (such as the square root of six) have endless decimal points, so you would have to end up rounding it off. It would be less precise then, than a simplified answer. *no help* *sorry*

[Xuut]

No, we were told not to have negative exponents (and we were given this before the exponents unit so using exponents would sort of be not possible) and not to have radicals in the denominator.

So I think we need to rationalize and then divide...

Or something.

I'll just ask tomorrow.

But thanks. :)

[Hannah]

Ohhh... Get the radical out of the denominator? *totally forgot those weren't allowed*

[nathan_p]

It has been a long time since I learned how to do this (which, okay, since I didn't get it the first time around was this spring), but I'll have a go.

The decimal is not your simplified answer. Your simplified answer will involve a radical somewhere. (But, yes, if you work out THAT radical, you'll get the decimal.)

So, the first thing you do is reduce the numbers outside the radicals. (However, here you can't do that since five is an odd number.)

After that, you do some other stuff (which we don't have to do here since this is fairly simple), but... I'm going to go with "this is a trick question"*.

*Especially if your teacher specified that the answer has to be in radical form. To be safe, I would probably work out the decimal number to about four figures after the decimal point and put that.

...However. Disclaimer. I have a terrible memory and I have never been good at radicals. But I hope this helps a little bit?

[Xuut]

I think I'm to rationalize it... And then divide the leftovers.

I've went to those Math sites that give you the answer and I haven't a clue how they got it.

And he never said they had to be in radical form, just not decimals. It can be in fractions or whatever, just not decimals.

[Fate]

My wonderful calculator gave me the answer of 10 times the square root of 6 + 4 time the square root of three all divided by 23. How did it get that? I have no idea. I think it multipled the top and the bottom by the denominator.

[EndOfTheEarth]

Multiply top and bottom by the quantitiy (5+root2)

The result will put all the roots in the numerator.

It will give you (10root6-4root2)/23
I'm not sure if that's what she's looking for, but if she just wants you to bring the roots up, that's how you do it.
(In brief, this won't ever give you a pretty answer. Stop using your calculator, it is nearly useless past this point)

[Xuut]

Okay, that's what my mom kept telling me to do. Thanks.

As for the decimal thingee....

I mean when you punch in say, 10√6 - 4√2 / 23 I get a random amount of numbers in my calculator.

Shouldn't the random decimal number of 10√6 - 4√2 / 23 be the same as the random decimal number of 2√6 / 5-√2 ? Because I've done it for the rest of my questions and when they aren't equivalent, it generally means my answer is wrong.

Also... How did it become subtract 4√2? Shouldn't it be plus?

[EndOfTheEarth]

Right, plus. This is what usually killed me in math class. I'd do all the work right, except for a plus or minus somewhere.

Is this on a graphing calculator, or a calculator that allows you to set groups of quantities? If not, your calculator will perform the wrong operation (In short (10√6 + 4√2)/23, or rather (10√6/23) + (4√2/23) is not the same as if you were to just punch in 10√6 + 4√2/23 on a cheap calculator, as it would perform it in a different way, or even if you did it on the graphic calculator without defining your quantities, it would still give you a separate answer. Same goes for the original entry, your calculator may be misinterpreting it as (2√6 / 5)-√2

[Xuut]

Same. It's why I always double check with my calculator. I don't trust myself enough.

Oh, yeah I learned that pretty quickly. I know that the calculator will always follow order of operations. So I always bracket the top numbers then put the division sign then bracket the bottom numbers or it'll divided everything first and my answers will be wrong.

[Ovie! Ovie! Ovie! Oy! Oy! Oy!]

So I'm supposed to design my own personal swim warm up for my next class on thursday.
It's 8 lengths of a 25m length pool.
Now the only swim method I'm good at is front crawl, so should I...
a) do a bunch of variations of front crawl and go about 90-100% efficiency for most of it... or
b) do methods I'm worse at like backcrawl or breast-stroke and be stuck at only about 50% of what I could achieve?

[Contradiction]

1. So it's just a warm up?
2. Are you being graded?
3. If ^yes, on time or on getting it done?

I dunno, I'd probably do half crawl, half other stuff if time wasn't being graded. 'Cause the only way you'll get better at the other stuff is by swimming them...