# Dividing powers with the same base

• Nov 2nd 2013, 10:16 AM
Mukilab
Dividing powers with the same base
I'm trying to do

$\displaystyle \frac{e^{-3.15x10^{18}}}{e^{-4.9x10^{17}}}$

Can I minus the powers so I get

$\displaystyle e^{-2.66x10^{18}}$
• Nov 2nd 2013, 10:30 AM
Plato
Re: Dividing powers with the same base
Quote:

Originally Posted by Mukilab
I'm trying to do
$\displaystyle \frac{e^{-3.15x10^{18}}}{e^{-4.9x10^{17}}}$
Can I minus the powers so I get
$\displaystyle e^{-2.66x10^{18}}$

Yes you can. But what is $\displaystyle -3.15\cdot 10^{18}+4.9\cdot 10^{17}~?$
• Nov 2nd 2013, 10:31 AM
grillage
Re: Dividing powers with the same base
Yes, you can do this.
• Nov 2nd 2013, 11:46 AM
HallsofIvy
Re: Dividing powers with the same base
Quote:

Originally Posted by Plato
Yes you can. But what is $\displaystyle -3.15\cdot 10^{18}+4.9\cdot 10^{17}~?$

It is $\displaystyle (-31.5+ 4.9)\cdot 10^{17}= -26.6 \cdot 10^{17}= -2.66 \cdot 10^{18}$ just as Mukilab had!

(However, Mukilab, "minus" is NOT a verb! Subtract the two.)
• Nov 2nd 2013, 04:14 PM
Mukilab
Re: Dividing powers with the same base
Quote:

Originally Posted by HallsofIvy
It is $\displaystyle (-31.5+ 4.9)\cdot 10^{17}= -26.6 \cdot 10^{17}= -2.66 \cdot 10^{18}$ just as Mukilab had!

(However, Mukilab, "minus" is NOT a verb! Subtract the two.)

Haha thanks, I'll keep that in mind.