Lesson 4 Log-Arithm-etic Practice Understanding

Ready

1.

Factor out the greatest common factor in the expression. Then simplify the numbers inside the parentheses.

Factor out the GCF

Factored Form

Simplified Expression

2.

Jaxon has invested in an excellent money market account that earns per year. Given is a chart of his year-end balances that appeared on his investment statements.

Beginning Balance

End of year

End of year

End of year

Jaxon’s money is growing exponentially, and he recalls from a previous math class that the formula for an exponential function is . He recalls that and . He thinks should equal , but that number isn’t giving him the numbers on his bank statement. What number should he be using for ? Explain.

3.

Jackie owes on a loan. She has agreed to pay the loan company of the outstanding balance on the first day of each month. Given is a chart of the balances she owes after each payment.

Initial Amount Owed

Month 1

Month 2

Month 3

Jackie knows her loan balance is decreasing exponentially. She also recalls from a previous math class that the formula for an exponential function is . She replaces with and lets be the number of monthly payments. But when she uses in the formula for , it doesn’t give her the correct balance for each month. What number should she be using for ? Explain.

Set

Use properties of logarithms to rewrite the indicated logarithms in terms of the given values, then find the indicated logarithm using the given approximate values.

Do not use a calculator to evaluate the logarithms.

Given:

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Find

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Find

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Find

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Find

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Find

Given:

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Find

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Find

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Find

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Find

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Find

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Find

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Find

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Find

Go

Use your calculator and the definition of to find the value of . (Round your answers to four decimals.)

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