SOLUTION: How would you go about finding when the percent of foreign born citizen was at its highest and when it was at its lowest percent since 1990?
The U.S. population that was foreig
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The U.S. population that was foreig
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Question 1036215: How would you go about finding when the percent of foreign born citizen was at its highest and when it was at its lowest percent since 1990?
The U.S. population that was foreign-born since 1900 can be modeled by where t = 0 in 1990.
Here is the graph of the polynomial function: http://postimg.org/image/hz7mo786z/ Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! where t = 0 in 1990.
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Find the 1st derivative.
P'(t) =
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Solve the quadratic for t, the times of local max and min.
Quadratic equation (in our case ) has the following solutons:
For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=0.00016 is greater than zero. That means that there are two solutions: .
Quadratic expression can be factored:
Again, the answer is: 74.0253073352042, 3.75247044257356.
Here's your graph:
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t = x + 1900
--> 1903 & 1974
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You can see on the graph the 1903 is the max and 1974 is the minimum.
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To determine whether it's a max or min, find the 2nd derivative of P(t)
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P"(t) =
P"(3) = = -0.01292
< 0 --> maximum
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P"(74) = 0.01264
> 0 --> minimum
