Suppose you purchase an iphoneX for $720 when it initially launched. The resale value decreases 3.08% each month since launch. Write an exponential function that models this situation, where t is the number of months after launch. Call it P(t). (round to the nearest thousandth.)

Question
Exponential models
asked 2021-02-08
Suppose you purchase an iphoneX for $720 when it initially launched. The resale value decreases 3.08% each month since launch. Write an exponential function that models this situation, where t is the number of months after launch. Call it P(t). (round to the nearest thousandth.)

Answers (1)

2021-02-09
Given,
Suppose you purchase an iPhone X for $720 when it initially launched. The resale value decreases 3.08% each month since launch.
So, the price of the iphoneX after 1 month \(=((100-3.02)/100)*720\)
=0.9692*720
Again,the price of the iphoneX after 2 months \(=((100-3.08)/100)*0.9692*720\)
=0.9692^2*720
Therefore, the price of the iphone X after t month \(=0.9692^t*720\)
\(=0.97^t*720\)
\(p(t)=0.97^t*720\)
0

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