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Logarithms and composite functions

Pick best answer: For the given pair of functions
1.) f= 5x-1 and g=x^2, find fog(2)
a. 81 b. 19 c. 5x^2-1 d. (5x-1)^2

2.) f= 2x^2 and g=x+1, find gof(x)
a. gof(x) = 2(x+1)^2 b. gof(x) = 2x^2 +1 c. gof(x) =2x^2 +x +1 d. gof(x) = not given

3.) Simplify: 10^log(1000) a. 3 b. 1,000 c. -3 d. 1,000,000

Please answer:
1.) f= 3x-1 and g= 2x+4, find (f/g)(x) and its domain.
2.) If an account has an annual yield of 5% compounded quarterly, how long before the account triples?
3.) My money decays at a rate of .24 of its original amount per year. I am worried, because this means the equation M=A(.76)^t, where t is the time in years, gives the amount of my money after some time has elapsed. Find how long it would take for my money to shrink to a quarter of its original amount.
4.) How long does it take for an account earning 12% per year compounded annually to grow to $7,000 if you invest $2,500?
5.) We deposit $4,000 into an account with an annual yield of 8% compounded annually and $2,500 into another account with an annual yield of 9 1/2% compounded annually. How long before the second account is equal to the first account?

Solution Summary

There are several problems here involving logarithms, compound interest, and composite functions.