Expert: Richard J. Raridon - 4/11/2009

Question
QUESTION: A certain species of deer is to be introduced into a forest, and wildfire experts estimate the population will grow to P(t)=(179)2^t/3 where t represents the number of years from the time of introduction?  How do you solve this without a calculator.  I cannot seem to find a button on it that shows me the exponential.  My question is is there another way tha t you can solve it by using lograthims instead of exponentials if you dont have a calculator button where you can get the results of an exponential?  How using this problem above do you solve it?  Thanks

ANSWER: Most calculators have a y^x button.  Just put in 2, hit y^x, put in the value for t/3 and hit =.  Or you can use logs but y^x is simplier.  For example, if t = 1, P(1) = 226

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QUESTION: In your answer you said Most calculators have a y^x button.  Just put in 2, hit y^x, put in the value for t/3 and hit =.  Or you can use logs but y^x is simplier.  For example, if t = 1, P(1) = 226--what if your calculator doesnt have an x^y button on it?  How do you figure it out using logs and what is the formula for using i t with logs?

 



ANSWER: logP(1) = log179 + (1/3)log2 = 2.3531
10^2.3531 = 225.5

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QUESTION: You said in your first response that most calculators have a y^x button.  I have both a tI-36X solar and a TI-34.  Do you know where the y^x button would be located in either of these two calcularots?  I am having problems locating it on the calculator.  Or do I need a different calculator?

Answer
I am using a TI-35 Plus calculator that I've had for years. Every key has two functions.  The first functions across the top row are
x^2, log and lnx.  2nd row - hyp, sin, cos, tan, DRG.  3rd row
y^x, 1/x, a, b, divide.  Do you not have a first or second function listing y^x?  I'd be surprised if you don't have it on either of your calculators.