I'm back for my final week...

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Okay, I am doing reviews here getting ready for the final...

As I said before this is theworst text I have ever had the misfortune to own.

I am going over exponents.

(r^4)^2 Denis please make note of the brackets. :)
over
(r^5)^3

We have a sample like this in the book which is (t^2)^5 over (t^3)^4, they don't show how they arrived at it but the answer is 1/t^2 Can someone help me out with how to arrive at this answer?
 
Remember the property of exponents:

(a^m)^n=a^(mn)


So (r^4)^2=r^(4x2)=r^8 and (r^5)^3=r^(5x3)=r^15

Now the problem becomes

r^8/r^15=1/r^7

See if you can solve the problem with "t" using this technique.
 
Thank you everyone. Denis I will check out that site tonight. I ended up with an 85 on my midterm. Not bad, but I want to do better on the final. Talk to you tonight I'm sure. :lol:
 
Okay, I read that site. I understand what they were saying, my problem is that I don't know how to convert it to my sample problems.

For example:

w^-4 over w^6 According to the site when you have a negative it turns it into 1/w^4 over w^6 I am thinking I should add the exponents which would give me 1/w^10 correct?

(2x10^-9)*(4x10^23) Again, according to the site it says multipication should be treated as addition, so it would be 8x10^14 Correct?

These two confused me because I don't see them as mulitplication.
(2x10^-5)^3 I think I am suppose to multiply the exponents which would give me and cube the 2 which would give me 8x10^-15

And the last one is (-3x10^5)^3 The book gave me three choices for this one.
2.7x10^-16
27x10^16
-2.7x10^16

I have NO idea how any of these answers were arrived at. Any help would be appreciated.
 
bethany3168 said:
w^-4 over w^6...I am thinking I should add the exponents which would give me 1/w^10 correct?
Click to expand...
Yes.

bethany3168 said:
(2x10^-9)*(4x10^23)...it would be 8x10^14 Correct?
Click to expand...
Yes.

bethany3168 said:
(2x10^-5)^3 I think...8x10^-15
Click to expand...
Yes.

bethany3168 said:
And the last one is (-3x10^5)^3
Click to expand...
What is -3<sup>3</sup>? What is (10<sup>5</sup>)<sup>3</sup>? What is -3<sup>3</sup> when expressed in scientific notation? How does this combine with (10<sup>5</sup>)<sup>3</sup>?

Eliz.

P.S. THANK YOU for including your reasoning! :wink:
 
Well if I don't add my reasoning I will get confused. :) I have NO idea how you guys do it!

-3^3 would be -27 and (10^5)^3 gotta bracket for Denis :) would be 10^15

So now I have -27x10^15 since this is not one of the three choices, I assume I am not finished. I was wondering how they ended up with ^16. Are you allowed to multiply by -1 in order to make this a positive 27 and you would have to add one to the ^15 since you have to add during multiplication. Am I way off with that?
 
bethany3168 said:
I have NO idea how you guys do it!
Click to expand...
We're old, and have been doing this for a very long time. :wink:

bethany3168 said:
So now I have -27x10^15...
Click to expand...
Yes, but is "-27" in proper scientific-notation format?

Eliz.
 
Example:
12345x10^2 = 1234.5x10^3 = 123.45x10^4 = 12.345x10^5 = 1.2345x10^6
 
bethany3168 said:
Brilliant. 2.7x10^16
Click to expand...
Ahem! -2.7x10^16 :idea:

now, you will stay after class and clean the blackboards :twisted:
 
You tricked me! I should have known that the -27 would be -2.7. I was so happy that I thought I understood your example that I jumped the gun.

By the way I meant you were brilliant, not me.

How many blackboards do I owe ya??
 
Let us know how you do on your exam, Bethany. Good luck! :wink:
 
And modest too. Well now I know where atleast some of your brilliance came from. :) Happy, I promise I will check in to tell you how I did on my Final. I kind of feel like I am in that celluar commercial when the guy is walking around with his network. I hope you know which one I am talking about, but what I am saying is that I feel like you are all going in there with me. And I appreciate it more than I can say.
 
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