document.write( "Question 1036253: 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? \r
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\n" ); document.write( "The U.S. population that was foreign-born since 1900 can be modeled by \r
\n" ); document.write( "\n" ); document.write( " $\"+p%28t%29+=+0.00006t%5E3+-+0.007t%5E2+%2B+0.05t+%2B+14+\"$ where t = 0 in 1990. \r
\n" ); document.write( "\n" ); document.write( "Here is the graph of the polynomial function: http://postimg.org/image/hz7mo786z/ \n" ); document.write( "

Algebra.Com's Answer #650930 by Aldorozos(172) $\"\"$ $\"About$

You can put this solution on YOUR website!
This is a calculus problem. I give you some guidelines and hope it helps
\n" ); document.write( "First use Google to familiarize yourself with maximum and minimum using derivatives: Here is an example
\n" ); document.write( "https://www.mathsisfun.com/calculus/maxima-minima.html\r
\n" ); document.write( "\n" ); document.write( "We have to find the derivative of p(t) which is 3(.00006t^2)-2(.007t)+.05
\n" ); document.write( "We set this derivative to zero since at maximum the derivative is supposed to be zero 3(.00006t^2)-2(.007t)+.05 = 0 This is a quadratic equation. To solve it manually we can multiply all sides of the equation by 100,000 to get ride of the decimals and we end up having 3t^2-1400t - 5000 = 0
\n" ); document.write( "If we solve this equation we may gat t as 478
\n" ); document.write( "Now we have to set the t in our original equation to calculate the Y. By original equation, I means p(t). Of course this problem requires some calculation using calculator. \r
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