SOLUTION: Determine the constants N(o) and K so that the graph y=N(o)e^(kt) passes through the points (2,3) and (8,24). I dont even know how to start this problem... any help would be g

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: Determine the constants N(o) and K so that the graph y=N(o)e^(kt) passes through the points (2,3) and (8,24). I dont even know how to start this problem... any help would be g      Log On


   



Question 375947: Determine the constants N(o) and K so that the graph y=N(o)e^(kt) passes through the points (2,3) and (8,24).
I dont even know how to start this problem... any help would be greatly appreciated!!

Found 2 solutions by robertb, user_dude2008:
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
From the given point (2,3), 3+=+N%280%29e%5E%282k%29.
From the given point (8,24), 24+=+N%280%29e%5E%288k%29.
Raise the 1st equation to the 4th power, to get 3%5E4+=+%28N%280%29%29%5E4%2Ae%5E%288k%29, or 81+=+%28N%280%29%29%5E4%2Ae%5E%288k%29.
Divide this resulting equation by 24+=+N%280%29e%5E%288k%29, to get 81%2F24+=+27%2F8+=+%28N%280%29%29%5E3, resulting in N%280%29+=+3%2F2.
Hence 3+=+%283%2F2%29%2Ae%5E%282k%29, or 2+=+e%5E%282k%29, or k+=+ln2%2F2.

Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!
y=N(o)e^(kt)
3=N(o)e^(2k)
N(o)=3/e^(2k)


y=N(o)e^(kt)
24=(3/e^(2k))e^(8k)
24=3e^(6k)
8=e^(6k)
6k=ln(8)
k=ln(8)/6
k=3ln(2)/6
k=ln(2)/2
N(o)=3/e^(2k)
N(o)=3/e^(2*ln(2)/2)
N(o)=3/e^(ln(2))
N(o)=3/2

Answer: equation is y = 3/2 e^(ln(2)/2 t)