Need help with P(t) = [ 73t^(1/3) - 28t^(2/3) ] / t

stormer

New member
Joined
Jul 29, 2006
Messages
2
Can someone help me with this problem?

. . .P(t) = [ 73t^(1/3) - 28t^(2/3) ] / t

Should the top be written as a rational equation? 73 t cubed and 28t cubed??

Please help. Thank you!
 

stapel

Super Moderator
Staff member
Joined
Feb 4, 2004
Messages
15,943
Why would the numerator (an expression) be converted to another type of object (an equation)? Why would the cube roots turn into cubes?

What are the instructions for this? What are you trying to do? Please be specific. Thank you.

Eliz.
 

stormer

New member
Joined
Jul 29, 2006
Messages
2
Sorry about that.

This is a word problem that we are doing for extra credit. It is as follows:

According to the American Medical Association, the percentage of potential employees testing positive for ill eagle drugs on the decline.
The Function (P(t) = Insert equation here) models the percentage P(t), of people applying for jobs who test positive (t) years after 1985.
What percentage of people applying for jobs tested positive for illegal drugs in 1993?


Any help would be greatly appreciated
 

soroban

Elite Member
Joined
Jan 28, 2005
Messages
5,588
Hello, stormer!

According to the American Medical Association,
the percentage of potential employees testing positive for illegall drugs on the decline.

The function: \(\displaystyle \L P(t)\:=\:\frac{73t^{\frac{1}{3}}\,-\,28t^{\frac{2}{3}}}{t}\,\) models the percentage \(\displaystyle P(t)\)
\(\displaystyle \;\;\)of people applying for jobs who test positive \(\displaystyle t\) years after 1985.

What percentage of people applying for jobs tested positive for illegal drugs in 1993?

Your questions are scary . . .

Don't say "equation" unless you mean it.

We are given cube roots . . . you're asking about cubes?

\(\displaystyle 1993\) means \(\displaystyle t\,=\,8\) . . . Plug it in !

 

Denis

Senior Member
Joined
Feb 17, 2004
Messages
1,446
P(t) = [ 73t^(1/3) - 28t^(2/3) ] / t
Why are you complicating it?

t = 1993 - 1985 = 8

P(t) = [ 73 * 8^(1/3) - 28 * 8^(2/3)] / 8

8^(1/3) = 2 : 2*2*2 = 8
8^(2/3) = (8^2)^(1/3) = 64^(1/3) = 4 : 4*4*4 = 64

Finish it.
 
Top