document.write( "Question 967182: 1)Find the smallest integer p such that x^2-2x+p is always greater than 3. Show your working and explain clearly please. Also, can you explain clearly why the graph must be above the x-axis.Help pls.\r
\n" ); document.write( "\n" ); document.write( "2)Find the range of x that satisfies the inequality x^2-6x+9> or = to 0.
\n" ); document.write( " Please explain and show me the working step by step.\r
\n" ); document.write( "\n" ); document.write( "3)What is the quadratic inequality for the solution which x<-4 and x>8.Expain clearly and pls show me ur working. Thanks
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Algebra.Com's Answer #591148 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
#3:\r
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\n" ); document.write( "\n" ); document.write( "Quadratic is wanted so that solution set is the union of \"x%3C-4\" and \"x%3E8\". Something can be found EITHER for the quadratic being LESS THAN 0, OR GREATER THAN 0. The question is open for you to decide which way you want.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%28x-8%29%3C0\" has critical values of -4 and 8. What happens BETWEEN those value? Pick any x value between -4 and 8 and test it:\r
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\n" ); document.write( "\n" ); document.write( "Pick for convenience, x=0.
\n" ); document.write( "\"%280%2B4%29%280-8%29%3C0\"
\n" ); document.write( "\"4%2A%28-8%29%3C0\"
\n" ); document.write( "\"-32%3C0\"
\n" ); document.write( "This shows that the set of values for x between -4 and 8 will all make this inequality true; but what we want is not to have THAT as a solution set, because the question was, find the quadratic which has solution set OUTSIDE of \"-4%3Cx%3C8\".\r
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\n" ); document.write( "\n" ); document.write( "How do we find the requested quadratic expression?
\n" ); document.write( "How about \"%28x%2B4%29%28x-8%29%3E0\" ?
\n" ); document.write( "Will the solution set be the union of \"x%3C-4\" and \"x%3E8\" ?
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\n" ); document.write( "Test those intervals.
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\n" ); document.write( "Pick x=-5, which is within x<-4.
\n" ); document.write( "\"%28-5%2B4%29%28-5-8%29%3E0\"
\n" ); document.write( "\"%28-1%29%28-13%29%3E0\"
\n" ); document.write( "\"13%3E0\"
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\n" ); document.write( "Pick x=10, which is within x>8.
\n" ); document.write( "\"%2810%2B14%29%2810-8%29%3E0\"
\n" ); document.write( "\"24%2A2%3E0\"
\n" ); document.write( "\"48%3E0\"
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\n" ); document.write( "Both parts work.\r
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\n" ); document.write( "\n" ); document.write( "There is an answer. \"highlight%28%28x%2B4%29%28x-8%29%3E0%29\"\r
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\n" ); document.write( "\n" ); document.write( "#2:
\n" ); document.write( "Something seems wrong in the question, asking for \"range\" of x.\r
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\n" ); document.write( "\n" ); document.write( "#1:
\n" ); document.write( "You might find the use of the discriminant helpful.
\n" ); document.write( "\"x%5E2-2x%2Bp%3E3\"
\n" ); document.write( "\"x%5E2-2x%2Bp-3%3E0\"\r
\n" ); document.write( "\n" ); document.write( "A way to make the quadratic factorable can be expect p-3=1.
\n" ); document.write( "Then, p=4.
\n" ); document.write( "This would mean \"%28x-1%29%28x-1%29=x%5E2-2x%2B1%3E0\".
\n" ); document.write( "What happens at 1?
\n" ); document.write( "\"x%5E2-2x%2B%284-1%29%3E0\"
\n" ); document.write( "\"x%5E2-2x%2B3%3E0\"
\n" ); document.write( "(x-3)(x+1)>0
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\n" ); document.write( "We should probably want the discriminant to always be negative, so that the quadratic will never cross the x-axis.
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\n" ); document.write( "Back to \"x%5E2-2x%2Bp-3%3E0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282%5E2-4%2A%28p-3%29%29%3C0\"------the left member IS the discriminant.
\n" ); document.write( "\"4-4p-12%3C0\"
\n" ); document.write( "\"-4p-8%3C0\"
\n" ); document.write( "\"-4p%3C8\"
\n" ); document.write( "\"highlight%28p%3E2%29\"-----------this makes sure the quadratic does not have x-intercepts.\r
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\n" ); document.write( "\n" ); document.write( "An integer is wanted, for p, so that it is AS SMALL as possible. That would be \"highlight%28highlight%28p=3%29%29\".\r
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\n" ); document.write( "\n" ); document.write( "The answer should be checked to be sure.
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