Carbon-14 is a radioactive form of carbon that is found in all living plants and animals. After a plant or animal dies, the radiocarbon disintegrates. Scientists determine the age of the remains by comparing the amount of carbon-14 present with the amount found in living plants and animals. The amount of carbon-14 present after x years is modeled by the exponential function f(x)=A0e−0.0001216x, where A0 represents the initial amount.
Suppose a mummy from a certain country is discovered in which the amount of carbon-14 present is only about two-fifths the amount found in living human beings. About how long ago did the person die?
To find out how long ago the person died, we need to find the value of x when f(x) is equal to two-fifths (2/5) of the initial amount, A0.
We can set up the equation:
2/5 = A0 * e^(-0.0001216x)
Let's solve for x:
2/5 = e^(-0.0001216x)
To solve for x, we can take the natural logarithm of both sides of the equation:
ln(2/5) = ln(e^(-0.0001216x))
Using the properties of logarithms, we can bring down the exponent:
ln(2/5) = -0.0001216x
Now, we can isolate x:
x = (ln(2/5))/(-0.0001216)
Using a calculator, we can evaluate the right side to find:
x ≈ 11476.7 years
Therefore, the person died approximately 11,476.7 years ago.
To determine how long ago the person died, we need to solve for x in the equation:
f(x) = A0e^(-0.0001216x)
Given that the amount of carbon-14 present in the mummy is two-fifths (2/5) of the amount found in living human beings, we can set up the following equation:
(2/5)A0 = A0e^(-0.0001216x)
Let's solve for x by isolating it on one side of the equation. First, divide both sides of the equation by A0:
(2/5) = e^(-0.0001216x)
Take the natural logarithm (ln) of both sides to remove the exponential function:
ln(2/5) = ln(e^(-0.0001216x))
Using logarithm properties, we can bring down the exponent:
ln(2/5) = -0.0001216x * ln(e)
Remember that ln(e) is equal to 1, so the equation simplifies to:
ln(2/5) = -0.0001216x
Next, divide both sides of the equation by -0.0001216:
x = (ln(2/5)) / -0.0001216
Using a calculator, we can compute the value of x to find the approximate time since the person died.
To determine how long ago the person died, we need to find the value of x in the exponential function f(x) = A0e^(-0.0001216x), where A0 represents the initial amount of carbon-14 present.
Given that the amount of carbon-14 present in the mummy is about two-fifths (2/5) of the amount found in living human beings, we can set up the equation:
2/5 = e^(-0.0001216x)
To solve for x, we can take the natural logarithm (ln) of both sides of the equation:
ln(2/5) = ln(e^(-0.0001216x))
Using the property of logarithms, ln(e^x) = x, the equation becomes:
ln(2/5) = -0.0001216x
Dividing both sides of the equation by -0.0001216 gives:
x = ln(2/5) / -0.0001216
Using a calculator, we can determine that ln(2/5) is approximately -0.693. Substituting this value into the equation, we get:
x ≈ (-0.693) / -0.0001216
Simplifying, we find:
x ≈ 5692 years
Therefore, the person likely died approximately 5692 years ago.