document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1208350>Question 1208350</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Show that x^2 + 9 is prime.\r<BR>\n" );
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document.write( "I will first list the pairs of integers whose product is 9.\r<BR>\n" );
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document.write( "1, 9\r<BR>\n" );
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document.write( "-1, -9\r<BR>\n" );
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document.write( "3, 3\r<BR>\n" );
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document.write( "-3, -3\r<BR>\n" );
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document.write( "2. Compute their sums.\r<BR>\n" );
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document.write( "1 + 9 = 10\r<BR>\n" );
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document.write( "-1 + (-9) = -10\r<BR>\n" );
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document.write( "3 + 3 = 6\r<BR>\n" );
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document.write( "-3 + (-3) = -6\r<BR>\n" );
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document.write( "I can also say x^2 + 9 = x^2 + 0x + 9 and none of the sums added above equal 0. This leads me to conclude that x^2 + 9 is prime.\r<BR>\n" );
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document.write( "1. Do you agree?\r<BR>\n" );
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document.write( "2. How is this done for a trinomial?\r<BR>\n" );
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document.write( "Sample:\r<BR>\n" );
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document.write( "Show that x^1 + x + 1 is prime. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #846734 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=846734\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "You have the correct reasoning for problem 1. <BR>\n" );
document.write( "x^2+9 cannot be factored into the form (x+a)(x+b) where a,b are integers.<BR>\n" );
document.write( "A polynomial is considered prime if we cannot factor it any further.\r<BR>\n" );
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document.write( "The x^1 + x + 1 you wrote out should be something like x^2 + x + 1<BR>\n" );
document.write( "A similar question found <a  rel=nofollow HREF=\"https://www.algebra.com/algebra/homework/Polynomials-and-rational-expressions/Polynomials-and-rational-expressions.faq.question.1207338.html\">here</a><BR>\n" );
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