document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=25822>Question 25822</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find a formula for the exponential function f(x)=ab^x satisfying the given conditions:\r<BR>\n" );
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document.write( " f(3)=-3/8<BR>\n" );
document.write( " f(-2)=-12 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #14408 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=14408\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f(x)=ab^x<BR>\n" );
document.write( "f(3)=ab^(3)=-3/8<BR>\n" );
document.write( "f(-2)=ab^(-2)=-12<BR>\n" );
document.write( "Divide the 2nd equation into the 1st to get:<BR>\n" );
document.write( "b^5=[-3/8/-12]=1/32<BR>\n" );
document.write( "b=1/2<BR>\n" );
document.write( "Substitute that into ab^3=-3/8<BR>\n" );
document.write( "a(1/2)^3=-3/8<BR>\n" );
document.write( "a/8=-3/8<BR>\n" );
document.write( "a=-3<BR>\n" );
document.write( "Solution is a=-3; b=1/2<BR>\n" );
document.write( "You could check that answer in the equation ab^-2=-12<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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