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organize your thoughts.
A population of bacteria every hours. If the culture started with , write the
equation that models the bacteria population after hours.
There is initially grams of element . The half-life of element is years. Describe the
amount of element remaining as a function of time, , in years. Use as the base of
your exponential model and exact values.
The exponent’s coefficient is not nor is it . To find the correct coefficient, take the
base exponential equation , use what you know about the half-life time and amount,
then solve the equation for . If you are having trouble, refer back to the objective on
”Solving exponential equations”. Do not use a calculator - use exact values to get a
correct answer.
The half-life of carbon-14 is 5,730 years.
Part A. Describe the amount of carbon-14 remaining after years. The initial
amount of carbon-14, , is already included below.
Part B. Solve the equation above for written in terms of the ratio of carbon-14
remaining, .
Part C. The equation above is used to carbon-date objects. To solidify this idea, use
the model in Part B. to solve the following problem.
A bone fragment is found that contains of its original carbon-14. To the nearest year,
how old is the bone?
Part A. The exponent’s coefficient is not nor is it . To find the correct coefficient,
take the base exponential equation , use what you know about the half-life time and
amount, then solve the equation for . If you are having trouble, refer back to the
objective on ”Solving exponential equations”. Do not use a calculator - use exact
values to get a correct answer.
Part B. Now that you found the exponent’s coefficient, you have modeled the
general equation as . Since it asks you to rewrite the equation in terms of , start by
converting the equation into one with instead of and . Then, solve the equation for
.
Part C. What does represent? If we know this, then we could use the equation you
built in Part B. to solve for the age of the bone.
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Start typing the name of a mathematical function to automatically insert it.
(For example, "sqrt" for root, "mat" for matrix, or "defi" for definite integral.)