document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1065734>Question 1065734</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Let A be a finite set, and define by  f: P(B) -> N(non-negative integers) by f(B) = |B|.  <BR>\n" );
document.write( "     That is, f  takes a subset of A as an input and outputs the cardinality of that subset. \r<BR>\n" );
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document.write( "         a)  Is f injective?    Prove your answer.<BR>\n" );
document.write( "         b)  Is f surjective?   Prove your answer.<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 #680969 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52878)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=680969\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "You MUST define \"who is B\" and \"who is P\" to make your formulation correct.\r<BR>\n" );
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document.write( "I am not going to make this job instead of you.\r<BR>\n" );
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document.write( "I perfectly understand what you were going to say, but, for educational purposes, want you make your writing correct.\r<BR>\n" );
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