# (Apologies) Math exam today

• Dec 16th 2009, 08:29 AM
DannyMath
(Apologies) Math exam today
Hi guys,

I guess my old post got closed cause I was asking for general questions. I don't mean to violate any rules so I will keep my questions more specific. Exam is in few hours. If it's ok I'll keep my queries to this specific thread as to not flood the forums HAHA.

I'm working on this exercise teach gave for homework (I don't know how to write mathematically online): 1/(3^-1-4^-1)

His answer is 12, but mine is -1, is there something amiss? (This is just beginning of my confusion HAHAHAHA)
• Dec 16th 2009, 09:03 AM
masters
Quote:

Originally Posted by DannyMath
Hi guys,

I guess my old post got closed cause I was asking for general questions. I don't mean to violate any rules so I will keep my questions more specific. Exam is in few hours. If it's ok I'll keep my queries to this specific thread as to not flood the forums HAHA.

I'm working on this exercise teach gave for homework (I don't know how to write mathematically online): 1/(3^-1-4^-1)

His answer is 12, but mine is -1, is there something amiss? (This is just beginning of my confusion HAHAHAHA)

Hi DannyMath,

$\displaystyle \dfrac{1}{3^{-1}-4^{-1}}=\dfrac{1}{\frac{1}{3}-\frac{1}{4}}=\dfrac{1}{\frac{4}{12}-\frac{3}{12}}=\dfrac{1}{\frac{1}{12}}=12$