d2jsp
Gaming and Trading Community
Gaming and Trading Community
Hourly Raffle
Ladder Slasher
Trade Finder
Photo Gallery
Forum Gold FAQ
Instant Messenger
Help and Rules
Live Streams
Account RecoveryResend Validation Email
Hello, GuestLog InRegister
d2jsp Forums > General Chat > Homework Help Hotline > Quick Algebra Help

Add ReplyNew TopicNew Poll
Page 1 of 1
furbyjs
#1 Aug 20 2012 07:36pm
Group: Members
Posts: 4,751
Joined: Jul 4 2009
Gold: 1,837.00
I just started my first college calc class, and I cannot remember anything from Algebra....

What I need to know right now is.....

So I have (81x^-4 * y^8)^-1/4 * (xy^1/4)
All I need to do is simplify.
This is what I went to.

((x^4/81y^8))^1/4 * (xy^1/4)

I'm not sure if this is right so far. If it is, I don't know what to do next. I was thinking that I could distribute the fourth root to each thing inside the parentheses (if I can do that??) so it would be (x/3y^2) * (xy^1/4)

Anyway, that's all I really need to know right now.
Your help is appreciated, thanks!
carteblanche
#2 Aug 20 2012 07:44pm
Group: Members
Posts: 18,870
Joined: Jul 23 2006
Gold: 2,461.00
fyi, if you're wondering whether two expressions are equal, i recommend using a calculator and picking some values for x and y (eg: 2 and 3), sticking it into both expressions, and seeing if it's equal. there's a chance for false positives (eg your numbers worked out coincidentally) but if the two expressions come out with different values then they're not equivalent.
furbyjs
#3 Aug 20 2012 07:52pm
Group: Members
Posts: 4,751
Joined: Jul 4 2009
Gold: 1,837.00
We aren't supposed to use calculators, and I don't have one anyway. I guess I could use wolfram alpha, but I would still like to know if I did it correctly.
kdog3682
#4 Aug 20 2012 08:56pm
Group: Members
Posts: 14,466
Joined: Jan 3 2008
Gold: 270,000.00
(81x^-4 * y^8)^-1/4 * (xy^1/4)

(ab)^x = a^x * b^x

Then: (81x^-4)^-1/4 * (y^8)^-1/4

a^x^y = a^(xy)

Then: 81^-1/4 * x^(-4*-1/4) = 81^-1/4 * x and y^(8*-1/4) = y^-2

81^-1/4 * x * y^-2 * x * y^1/4 = 81^-1/4 * x^2 * y^(-2+1/4)

Answer: 81^-1/4 * x^2 * y^(-1.75)
furbyjs
#5 Aug 21 2012 07:41am
Group: Members
Posts: 4,751
Joined: Jul 4 2009
Gold: 1,837.00
Uhm.... Where did you get the 1/4 from an exponent to multiplication?
furbyjs
#6 Aug 21 2012 08:42am
Group: Members
Posts: 4,751
Joined: Jul 4 2009
Gold: 1,837.00
(x/3y^2) * (xy^1/4)

Okay, So this is correct, but it needs to be in exponential notation. How would I do that?
DaemonPlayer
#7 Aug 21 2012 09:55am
Group: Banned
Posts: 1,413
Joined: Jul 31 2012
Gold: 0.00
Warn: 30%
Quote (furbyjs @ Aug 21 2012 10:42am)
(x/3y^2) * (xy^1/4)

Okay, So this is correct, but it needs to be in exponential notation. How would I do that?


(x^2)/(3y^(7/4))
furbyjs
#8 Aug 21 2012 11:59am
Group: Members
Posts: 4,751
Joined: Jul 4 2009
Gold: 1,837.00
That's it? I thought I tried that... I'll try again.
Go Back To Homework Help Hotline Topic List
Page 1 of 1