document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=409819>Question 409819</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you pls help me with the following:\r<BR>\n" );
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document.write( "Use the Change of Base Formula to evaluate each expression. Leave your answer in \"calculator ready\" format. \r<BR>\n" );
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document.write( "log_2&#8289;7\r<BR>\n" );
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document.write( "Thank you!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #288405 by </B><A HREF=/tutors/aboutme.mpl?userid=jsmallt9><B>jsmallt9(3758)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jsmallt9><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=288405\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%282%2C+%287%29%29 ALIGN=MIDDLE  ALT=\"log%282%2C+%287%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "No calculator I know of :knows\" base 2 logarithms. So the only way to express this logarithm in a way that your calculator can handle is to use the Change of Base Formula to change this base 2 logarithm into an expression involving logarithms your calculator does \"know\", like base 10 or base e (aka ln).<br><BR>\n" );
document.write( "The Change of Base Formula is:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28a%2C+%28p%29%29+=+log%28b%2C+%28p%29%29%2Flog%28b%2C+%28a%29%29 ALIGN=MIDDLE  ALT=\"log%28a%2C+%28p%29%29+=+log%28b%2C+%28p%29%29%2Flog%28b%2C+%28a%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "We can use this to change to base 2 logarrthm into an expression of base 10 logarithms:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28%287%29%29%2Flog%28%282%29%29 ALIGN=MIDDLE  ALT=\"log%28%287%29%29%2Flog%28%282%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "or base e logarithms:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%287%29%2Fln%282%29 ALIGN=MIDDLE  ALT=\"ln%287%29%2Fln%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Note: If you actually calculate both of these expressions you will find, believe it or not, that they are equal! </SPAN>\n" );
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