document.write( "Question 175746This question is from textbook Algebra 2
\n" ); document.write( ": How do I graph this polynomial function? f(x)=x^4 - 2x^3 - 3x^2 + 5x + 2.
\n" ); document.write( "Thank you very much.
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Algebra.Com's Answer #130891 by nabla(475)\"\" \"About 
You can put this solution on YOUR website!
1) Factor to f(x)=(-2 + x) (-1 - 3 x + x^3)
\n" ); document.write( "2) The first evident, real root will be x=2.
\n" ); document.write( "3) It should be noted that this will \"eventually\" resemble a parabola. Moreover, our interest will be around x=2.
\n" ); document.write( "4) Techniques of calculus will give us concavity, max, min, inflection.\r
\n" ); document.write( "\n" ); document.write( "f'(x)=4x^3-6x^2-6x+5=0 gives criticals of\r
\n" ); document.write( "\n" ); document.write( "x -> -1.05274
\n" ); document.write( "x -> 0.611731
\n" ); document.write( "x -> 1.94101\r
\n" ); document.write( "\n" ); document.write( "If you test outside the intervals you will note changes in direction of the slope this is indicative of extrema.
\n" ); document.write( "Thus: x=-1.05274 is local minimum
\n" ); document.write( "x=0.611731 is local maximum
\n" ); document.write( "x=1.94101 is local minimum\r
\n" ); document.write( "\n" ); document.write( "Concavity [not entirely necessary]:
\n" ); document.write( "f''(x)=12x^2-12x-6=0
\n" ); document.write( "gives
\n" ); document.write( "x -> -0.366025
\n" ); document.write( "x -> 1.36603\r
\n" ); document.write( "\n" ); document.write( "Testing intervals again you will find CU on (-inf, -0.366025), CD on (-0.366025, 1.36603), then CU on (1.36603, inf).\r
\n" ); document.write( "\n" ); document.write( "This is certainly enough information to produce the following graph:\r
\n" ); document.write( "\n" ); document.write( "\"graph%28+300%2C+200%2C+-3%2C+4%2C+-5%2C+10%2C+x%5E4-2x%5E3-3x%5E2%2B5x%2B2%29\"
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