document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=316365>Question 316365</A>: <I><SPAN STYLE=\"word-break: break-all;\"> State the domain for the function: f(x) = x/(x + 1) \r<BR>\n" );
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document.write( "A. {x: all real numbers}  <BR>\n" );
document.write( "B. {x: all real numbers except 0}  <BR>\n" );
document.write( "C. {x: all real numbers except –1}  <BR>\n" );
document.write( "D. {x: all real numbers except 1}   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #226379 by </B><A HREF=/tutors/aboutme.mpl?userid=moshiz08><B>moshiz08(60)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=moshiz08><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/cgi-bin/show-face.mpl?user=moshiz08><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=226379\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I know you had other questions, but can you please repost them separately as they belong in different subject areas? Sorry about the trouble. \r<BR>\n" );
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document.write( "So we have <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28x%29+=+x%2F%28x+%2B+1%29+ ALIGN=MIDDLE  ALT=\"f%28x%29+=+x%2F%28x+%2B+1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "Let's try to find f(1). So we plug in 1 for x to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+f%281%29+=+1%2F%281%2B1%29+=+1%2F2 ALIGN=MIDDLE  ALT=\"+f%281%29+=+1%2F%281%2B1%29+=+1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >. So 1 is in the domain. \r<BR>\n" );
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document.write( "Let's try to find f(0). So we plug in 1 for x to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+f%280%29+=+1%2F%280%2B1%29+=+1%2F1+=+1 ALIGN=MIDDLE  ALT=\"+f%280%29+=+1%2F%280%2B1%29+=+1%2F1+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" >. So 0 is in the domain. \r<BR>\n" );
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document.write( "Let's try to find f(-1). So we plug in -1 for x to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+f%28-1%29+=+1%2F%28-1%2B1%29+=+1%2F0+=+undefined ALIGN=MIDDLE  ALT=\"+f%28-1%29+=+1%2F%28-1%2B1%29+=+1%2F0+=+undefined\"   DISABLED_style= \"max-width:90%; height:auto;\" >. So -1 cannot be in the domain, because we cannot divide by 0. \r<BR>\n" );
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document.write( "Thus, the answer is C: all real numbers except for -1. \r<BR>\n" );
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document.write( "The general procedure to finding domain of a rational function is to set the DENOMINATOR equal to ZERO. Since we know that division by zero is not allowed, this will tell us the values at which the function is not defined. In this example, we have (x+1) in the denominator. Setting this equal to zero gives <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2B1+=+0 ALIGN=MIDDLE  ALT=\"x%2B1+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > which is true when x=-1. So we know that x=-1 makes the denominator equal to zero, and thus makes the function undefined, so -1 cannot be in the domain. Thus the domain is the set of real numbers except for -1. I hope this makes sense. Please do repost the other questions for us to take a look at. \r<BR>\n" );
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document.write( "CCAAD.  </SPAN>\n" );
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