document.write( "Question 1034396: 1. Sketch the graph of the polynomial function f(x) = ‒x4 + 5x3 + 9x2 ‒ 45x in the interval [‒4, 6].\r
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document.write( " 1) Write the polynomial function in factored form.
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document.write( " 2) Sketch the graph of the polynomial function, labeling key points on the graph.
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document.write( " 3) Describe the characteristics of the graph including: zeros, y-intercept, relative maximum and minimum and end behavior.
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document.write( "(3 points)\r
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document.write( "2. Sketch the graph of the polynomial function f(x) = ‒x3 ‒ 4x2 + 4x + 16 in the interval [‒5, 3].\r
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document.write( " 1) Write the polynomial function in factored form.
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document.write( " 2) Sketch the graph of the polynomial function, labeling key points on the graph.
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document.write( " 3) Describe the characteristics of the graph including: zeros, y-intercept, relative maximum and minimum and end behavior.
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document.write( "(3 points)
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document.write( "3. Use what you have learned about the Remainder Theorem to show that X +1 is a factor of 19x42 + 18x -1.\r
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document.write( "(3 points)
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Algebra.Com's Answer #649206 by KMST(5328)![]() ![]() You can put this solution on YOUR website! 1. \n" ); document.write( "1) Notice that two \"parts\" of the polynomial share \n" ); document.write( " \n" ); document.write( "then factor by parts. \n" ); document.write( " \n" ); document.write( "Alternatively, youu could take \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "2) and 3) Each teacher/ instructor may have slightly different expectations about how to \"sketch the graph of the polynomial function, labeling key points on the graph\", but the calculations needed for the sketch would involve finding the values of \n" ); document.write( "The y-intercept is easy: \n" ); document.write( "For \n" ); document.write( "so we can say that the y-intercept is \n" ); document.write( "We know that the point \n" ); document.write( "The \"end behavior\" we are concerned with for the sketch in the interval \n" ); document.write( "Since \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "In general, the end behavior of a function involves limits, \n" ); document.write( "but in the case of polynomials, \n" ); document.write( "we learned early in algebra that the end behavior is determined by \n" ); document.write( "the leading coefficient (whether it is positive or negative), and \n" ); document.write( "the degree of the polynomial (whether it is even or odd). \n" ); document.write( "A polynomial's end behavior is the same as the end behavior of its first term, \n" ); document.write( "so \n" ); document.write( "(The polynomial is negative at both \n" ); document.write( "as we go towards those ends, the polynomial's absolute value increases without bounds). \n" ); document.write( "The zeros are obvious from the factored form of the polynomial, \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "At each one of those zeros, the factor involved changes sign, and so does the function, so \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "That is useful information for your sketch, \n" ); document.write( "and would lead you to conclude that the polynomial must have \n" ); document.write( "a relative maximum in the interval \n" ); document.write( "a relative minimum in the interval \n" ); document.write( "a relative maximum in the interval \n" ); document.write( "To locate those relative maxima and minimum, \n" ); document.write( "we need the derivative, and we need to calculate the zeros of the derivative. \n" ); document.write( "The derivative is \n" ); document.write( "That polynomial cannot be factored, but it must change signs at least once, \n" ); document.write( "because its degree is \n" ); document.write( "In fact, it is not hard to see that it changes signs \n" ); document.write( "for \n" ); document.write( "for \n" ); document.write( "for \n" ); document.write( "for \n" ); document.write( "So it must have \n" ); document.write( "because we cannot factor it. \n" ); document.write( "We cannot find any rational zeros of the form \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "All we can do is use a calculator to find that the zeros of derivative. \n" ); document.write( "A graphing calculator (if we know how to use it) would make it easier, \n" ); document.write( "but with any calculator (or a spreadsheet) we can try values to \"zero in\" on those zeros, \n" ); document.write( "and find that the zeros of derivative \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "We can use the calculator to find the value of \n" ); document.write( "That tells you to include the points \n" ); document.write( " \n" ); document.write( "So far, you have 8 points of your sketch: \n" ); document.write( " \n" ); document.write( "For a sketch, all you have to do is join those points with a smooth curve, like this: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "2. \n" ); document.write( "1) The rational zero theorem tells us that a rational zero of that polynomial must be of the form \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "The choices are -16, -8, -4, -4, -2, -1, 1, 2, 4, 8, and 16. \n" ); document.write( "Trying them , starting with the easy ones, we find that \n" ); document.write( "However, \n" ); document.write( "we get \n" ); document.write( "whose zeros are \n" ); document.write( "So, \n" ); document.write( " \n" ); document.write( "2) and 3) Two points we need to include in the sketch are \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Other points for the sketch are zeros, y-intercept, minimum and maximum. \n" ); document.write( "The zeros of the function are \n" ); document.write( "Those zeros mark points \n" ); document.write( "also to be included in the sketch of the graph. \n" ); document.write( "The y-intercept is \n" ); document.write( "which tells you that \n" ); document.write( "The maxima and minima are zeros of derivative \n" ); document.write( " \n" ); document.write( "Those zeros are the solutions to \n" ); document.write( " \n" ); document.write( "The minimum and maximum of the function are \n" ); document.write( "approximately \n" ); document.write( "So, points \n" ); document.write( "also need to be included in the sketch of the graph. \n" ); document.write( "The sketch would look something like this: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "3) According to the Remainder Theorem, \n" ); document.write( "the remainder of the division of \n" ); document.write( "by \n" ); document.write( "Since that remainder is zero: \n" ); document.write( " \n" ); document.write( "and that means that \n" ); document.write( "or in other words that |