Question

u/(u-(u+1/2))=4

Answer 1

\[u\left/\left(u-\left(\frac{1}{2}+u\right)\right)\right.\text{=}4\]\[u\left/\left(-\frac{1}{2}\right)\right.\text{=}4\]\[-2 u\text{ = }4\]\[u\to -2 \]

Answer 2

u/[u-(u+1/2)]=4
u/(u-u-1/2)=4
u/-1/2=4
-2u=4
u=-2

Answer 3

answer book says the answer is 2...

Answer 4

Either the answer book is wrong or the problems is written incorrectly. Since 1/2 is
-1/2, you will get a negative u.

Answer 5

If you substitute what the answer book has, then the answer will be -4 and not 4.

Answer 6

well... i'm having trouble writing an equation like this on the computer. but the (u-(u+1/2) is written as u - u +1 over 2.... make sense?

Answer 7

With the negative in front of (u+1/2), then u becomes -u and the +1/2 becomes
-1/2.

Answer 8

i wish i could figure out the equation thing
the u+1 is over the 2. and you're subtracting the whole thing from u...

Answer 9

If the equation is meant to be the following:

u/(u-u+1/2)=4 then u=2 is correct.

Answer 10

i guess i need to figure out the equation button and re-post my question

Answer 11

Plug in 2 for u in the problem expression. At the end of the evaluation process Mathematica tells us that -4=+4, an invalid outcome. So u is not 2.\[\frac{u}{u-\left(u+\frac{1}{2}\right)}==4\text{/.}u\to 2 \]\[\frac{2}{2-\left(2+\frac{1}{2}\right)}==4 \]\[\frac{2}{2-\frac{5}{2}}==4 \]\[\frac{2}{\left(-\frac{1}{2}\right)}==4\]\[-4==4 \]

Answer 12

the (u+1/2) is not written correctly. it's (u+1)over 2. make sense?

Answer 13

According to your latest equation that (u+1)/2, then the equation should be as follows:

u/[u-(u+1)/2]=4
u/[(2u-u-1)/2=4
u/[(u-1)/2]=4
(u)[2/(u-1)]=4
2u/(u-1)=4
2u=4(u-1)
2u=4u-4 You can rewrite this equation as:

4u-4=2u
2u=4
u=2

Answer 14

my apologies for mistyping the equation initially

Answer 15

"the (u+1/2) is not written correctly. it's (u+1)over 2. make sense?"

The common convention in computer land is that multiplication and division take precedence over addition and subtraction. So I interpreted the subexpression of concern the way it was presented in my solution derivation.

I don't want to ruffle any feathers here, but nearly half the time the math expressions presented as problems on this web site are, strictly speaking, ambiguous. Hence the back and for over what the intent of your problem expression was. Notice that you added an addition ")" after the u+1 that was not in the original problem statement.

I use Mathematica 8 for calculations and normally send all math problem statements to WolframAlfa.com for their interpretation of the problem statements. Mathematica 8 has a direct connection with WoframAlfa through a drop down menue selection,
" Free- form input" for this purpose. I guess this is an example of "Cloud computing."

This is all I have to say on this matter.

Have a good day.