document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1006594>Question 1006594</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A function p(x) has a value of 5 when x>0 and a value of -5 when x<0.<BR>\n" );
document.write( "A function q is defined as q(x) = x^2 - 4.<BR>\n" );
document.write( "What is the value of (q(p(3))?\r<BR>\n" );
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document.write( "I get the answer:\r<BR>\n" );
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document.write( "Step 1. p(3) = 5 when 3>0 and -5 when 3<0.<BR>\n" );
document.write( "Step 2. q(5) = 5^2-4 = 21.\r<BR>\n" );
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document.write( "But why did I use 5 in step 2, and what does this mean? Could someone put it in words?\r<BR>\n" );
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document.write( "Thank you.<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 #622724 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=622724\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \"A function p(x) has a value of 5 when x>0 and a value of -5 when x<0.\"\r<BR>\n" );
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document.write( "is the same as saying\r<BR>\n" );
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document.write( "p(x) = 5 when x > 0<BR>\n" );
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document.write( "p(x) = -5 when x < 0\r<BR>\n" );
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document.write( "it depends on the value of x. If x is positive, then the function is p(x) = 5. OR, if x is negative, then p(x) = -5. It is impossible for p(x) to be both at the same time since x can't be both positive and negative at the same time.\r<BR>\n" );
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document.write( "We need to find p(3) first. This is p(x) when x = 3.<BR>\n" );
document.write( "x = 3 makes x > 0 true. Ie, 3 is positive<BR>\n" );
document.write( "so p(x) = 5 and p(3) = 5\r<BR>\n" );
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document.write( "Notice how we don't even bother with p(x) = -5 because x = 3 is NOT negative.\r<BR>\n" );
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document.write( "-----------------------------------------------------------------\r<BR>\n" );
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document.write( "now we plug that into q(x) like you did and we get \r<BR>\n" );
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document.write( "q(5) = 5^2-4 = 21\r<BR>\n" );
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document.write( "so q(p(3)) = 21 </SPAN>\n" );
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