document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1081255>Question 1081255</A>: <I><SPAN STYLE=\"word-break: break-all;\"> -1, -3, -1, 5, 15<BR>\n" );
document.write( "Find first differences for the sequence in order from a1 to a5. Determine whether or not the series is quadratic or not.\r<BR>\n" );
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document.write( "A.) , 2, 6, 10; not quadratic<BR>\n" );
document.write( "B.) 2, 2, 6, 10; quadratic<BR>\n" );
document.write( "C.) -2, 2, 6, 10; not quadratic<BR>\n" );
document.write( "D.) -2, 2, 6, 10; quadratic </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #695432 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=695432\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Calculate the first difference by subtracting,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5B1%5D=a%5B2%5D-a%5B1%5D=-3-%28-1%29=-3%2B1=-2 ALIGN=MIDDLE  ALT=\"d%5B1%5D=a%5B2%5D-a%5B1%5D=-3-%28-1%29=-3%2B1=-2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5B2%5D=a%5B3%5D-a%5B2%5D ALIGN=MIDDLE  ALT=\"d%5B2%5D=a%5B3%5D-a%5B2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5B3%5D=a%5B4%5D-a%5B3%5D ALIGN=MIDDLE  ALT=\"d%5B3%5D=a%5B4%5D-a%5B3%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5B4%5D=a%5B5%5D-a%5B4%5D ALIGN=MIDDLE  ALT=\"d%5B4%5D=a%5B5%5D-a%5B4%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Do the same for the remaining numbers.<BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
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document.write( "Then calculate the second difference.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D%5B1%5D=d%5B2%5D-d%5B1%5D ALIGN=MIDDLE  ALT=\"D%5B1%5D=d%5B2%5D-d%5B1%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D%5B2%5D=d%5B3%5D-d%5B2%5D ALIGN=MIDDLE  ALT=\"D%5B2%5D=d%5B3%5D-d%5B2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D%5B3%5D=d%5B4%5D-d%5B3%5D ALIGN=MIDDLE  ALT=\"D%5B3%5D=d%5B4%5D-d%5B3%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "If all the second differences are equal, the series is quadratic.<BR>\n" );
document.write( "Else it is not.<BR>\n" );
document.write( " </SPAN>\n" );
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