LF help with how to input a problem.

[Kilgannon]

Hey guys,

I am working through a practice test for an Econ class I am in, and I have no idea how to calculate this problem on my BA ii plus calculator (financial calculator, not a graphing calc). I took a picture of the formula, but I didn't include the inputs because I don't want people to think I am looking for someone to do my work for me. I am just totally confused lol.

anyways, here is the formula:



I am solving for r, but how do I calculate the...half root? I guess that is how you would name the (1/2) in the superscript of the square root. any advice on how to figure this out would be greatly appreciated! Thanks so much in advance!

---------- Post added 2012-10-23 at 04:48 PM ----------

Bump 10 char

[Auloria]

The 1/2 seems a bit redundant, since the "square root" already means "raise to power 1/2". I guess you are dealing with a lot of nth root problems and they are trying to make a clear distinction?

However, typically people denote "nth root" with an "n" set above the radical. Taken literally, the "1/2" in that case would mean you are actually squaring the term under the radical. Why would the exam be trying to trick you?

I give whoever made the exam an F. A "1/2" is completely inappropriate when used with a radical.

[Deleted]

Hey guys,

I am working through a practice test for an Econ class I am in, and I have no idea how to calculate this problem on my BA ii plus calculator (financial calculator, not a graphing calc). I took a picture of the formula, but I didn't include the inputs because I don't want people to think I am looking for someone to do my work for me. I am just totally confused lol.

anyways, here is the formula:



I am solving for r, but how do I calculate the...half root? I guess that is how you would name the (1/2) in the superscript of the square root. any advice on how to figure this out would be greatly appreciated! Thanks so much in advance!

---------- Post added 2012-10-23 at 04:48 PM ----------

Bump 10 char

Literally, that expression would be (2*b*Y/r)^2, since sqrt(x) is x^(1/2), third root x^(1/3) etc. But since that would be a very weird way of writing it, you need to guess what the mathematically challenged economist who wrote your test really wanted to write. I guess either sqrt(2*bY/r) or 1/sqrt(2*b*Y/r).

[Rukentuts]

The 1/2 seems a bit redundant, since the "square root" already means "raise to power 1/2". I guess you are dealing with a lot of nth root problems and they are trying to make a clear distinction?

However, typically people denote "nth root" with an "n" set above the radical. Taken literally, the "1/2" in that case would mean you are actually squaring the term under the radical. Why would the exam be trying to trick you?

I give whoever made the exam an F. A "1/2" is completely inappropriate when used with a radical.

That's what I thought as well basically saying 1/2 square root is like not saying anything at all. If it were the square root, it would say 2 sqrt, not 1/2 sqrt.

[Kilgannon]

Sorry for not replying sooner, got frustrated and just focused on some other things before going to take my test (this problem was off of a practice exam that was distributed in the previous class.)

Anyways, no similar problem showed up on the test, so it would seem he realized that this was a very confusing question to put on the exam. I am glad that those who are well versed in this area also had issues understanding the notation. Thankfully it wasn't an issue on the exam.

Thanks again for the responses!