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 Subject: "Divison of powers" Previous Topic | Next Topic
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Rachel
guest
May-06-02, 09:36 PM (EST)

"Divison of powers"

 I don't really under stand a simply and easy way to divide exponents without actually showing all the work. FOr example the problem 15^30/45^15 how could u find this answer this out actaully multipling the whole thing out does anything cancel each other out cause i don't understand how to use the powers laws because the bases and the exponents are both different??

bluediamond
Member since Apr-9-02
May-07-02, 01:52 PM (EST)

1. "RE: Divison of powers"
In response to message #0

 Well, by commutativity of multiplication, if ab = c, then axbx = cx. Thus, you can say 4515 = 1515315 and the problem reduces to 1515/315 which can be further reduced to 515. We could have obtained this directly by noting 1530 = 1515315515 = 4515515.Hope this helps,Dave

jrr7
guest
May-09-02, 02:57 PM (EST)

2. "RE: Divison of powers"
In response to message #0

 The key is being able to switch your view of the problem from "whole" to "a bunch of parts put together." This is common throughout mathematics.Don't just look at 15^30 as some huge, monolithic number. Keep it broken up into pieces you can understand.When you see division you should think "Factor it" and/or "multiply top and bottom by the same thing"