document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=913278>Question 913278</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what is the domain for y=4/x^2+1? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #554421 by </B><A HREF=/tutors/aboutme.mpl?userid=tutoringisfun><B>tutoringisfun(17)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tutoringisfun><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=tutoringisfun><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=554421\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Good Morning student. \r<BR>\n" );
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document.write( "Before I help you solve this problem, I feel that I have to review what we know about domains. When Y is a function of x, the domain is all the possible values for x. We cannot divide by 0 and we cannot take the root of a negative number. With those 2 rules in mind we can solve our problem. \r<BR>\n" );
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document.write( "y=4/x^2 + 1\r<BR>\n" );
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document.write( "since the denominator has an x in it we can set the denominator equal to zero and solve for x as follows:\r<BR>\n" );
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document.write( "x^2 + 1=0 we want to isolate x so we have to subtract 1 from each side:<BR>\n" );
document.write( "     -1 -1 this makes the 1's on the left cancel out and we are left with the following:\r<BR>\n" );
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document.write( "x^2= -1\r<BR>\n" );
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document.write( "to isolate x we have to take the square root of -1.\r<BR>\n" );
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document.write( "x=no real solution<BR>\n" );
document.write( "According to the rules above we cannot take the root of a negative number. There is no real number for this equation, only imaginary numbers. Therefore, x is any real number. \r<BR>\n" );
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document.write( "This means that the domain is all real numbers. It can be written in interval notation like this:<BR>\n" );
document.write( "(-inf,inf) inf means infinity. \r<BR>\n" );
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document.write( "I hope this was helpful to you. If you desire PAID assistance, you can contact me at http://www.prestoexperts.com/expert/marys-tutoring or via my facebook page listed in my profile or you may leave me a message via www.instaedu.com  Have a great day!\r<BR>\n" );
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