document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1155338>Question 1155338</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the function ​f(x)=ax^3+bx^2+cx+d for which, f(-3)=-112, f(-1)=-2, f(1)=4, f(2)=13.\r<BR>\n" );
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document.write( "I know the answer is f(x) 3x^3-4x^2+5\r<BR>\n" );
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document.write( "But, i would like to know how to solve this </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #777910 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=777910\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are 4 linear equations in 4 unknowns<BR>\n" );
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document.write( "(1)  -27a +9b -3c +d = -112<BR>\n" );
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document.write( "(2)  -a +b -c +d = -2<BR>\n" );
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document.write( "(3)  a +b +c +d = 4<BR>\n" );
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document.write( "(4)  8a +4b +2c +d = 13<BR>\n" );
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document.write( "Any of the following methods can be used, elimination method, substitution method, Gauss-Seidel method, Cramer's Rule<BR>\n" );
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document.write( "Note if you add equations 2 and 3 you get b +d = 1 and this can be used to eliminate a variable<BR>\n" );
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document.write( "   <BR>\n" );
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