document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1687>Question 1687</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Which of the following are functions  Expalin your reasoning for a,b,c.  Keep the definition of a fuction strongly in a mind as you do this problem.  Think about whether the relationship between f{x) and x is consistnet with being a function or not and explain your reasonong?\r<BR>\n" );
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document.write( "a.  f(x) = 2 if x>1<BR>\n" );
document.write( "    f(x) = -1 otherwise\r<BR>\n" );
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document.write( "b.  f(x)= 5 if x>0<BR>\n" );
document.write( "    f(x) = -5 if x <0<BR>\n" );
document.write( "    f(x) = 5 or -5 if x=0\r<BR>\n" );
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document.write( "c.  f(x)= 10/x<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #548 by </B><A HREF=/tutors/aboutme.mpl?userid=khwang><B>khwang(438)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=khwang><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=548\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) yes,f is a function from R to R. Since forevery real x,there exists a unique<BR>\n" );
document.write( "   f(x) corresponding to x.\r<BR>\n" );
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document.write( "b) No, since when x =0,f(0) is either 5 or -5(f(0) has no unique value.)\r<BR>\n" );
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document.write( "c)No,since x=0 causes the denominator to be zero,there is no value of f(0). </SPAN>\n" );
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