document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=921625>Question 921625</A>: <I><SPAN STYLE=\"word-break: break-all;\"> shown in the figure is a simple magnifier consisting of a convex lens. the object to be magnified is positioned so that its distance p from the lens than the focal length f. the linear magnification M is the ratio of the image size to the object size. it is shows in physics that M=f(f-p). if f=6 cm, how far should the object be placed from the lens so that its image appears at least three times as large?\r<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 #559258 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=559258\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You need to make <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=M=3 ALIGN=MIDDLE  ALT=\"M=3\"   DISABLED_style= \"max-width:90%; height:auto;\" > with a lens that has <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f=6 ALIGN=MIDDLE  ALT=\"f=6\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "Your formula is wrong. It should be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=M=f%2F%28f-p%29 ALIGN=MIDDLE  ALT=\"M=f%2F%28f-p%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "That way with numerator (f) and denominator (f-p) in the same units, you get a ratio of lengths for M.<BR>\n" );
document.write( "(I was once a high school physics teacher, and I also checked the formula to make sure my memory was not failing me after so many years of not teaching this stuff).<BR>\n" );
document.write( "Regardless of the formula, all you had to do was plug in the given values for M and f, and then solving for p.<BR>\n" );
document.write( "Plugging those values in you get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%3C=6%2F%286-p%29%7D%7D%0D%0ASolving%2C+ou+get%0D%0A%7B%7B%7B3%3C=6%2F%286-p%29%7D%7D+%0D%0A%7B%7B%7B3%286-p%29%3C=6%7D%7D%0D%0A%7B%7B%7B3%2A6-3p=6%29%7D%7D%0D%0A%7B%7B%7B18-3p%3C=6%29%7D%7D%0D%0A%7B%7B%7B18-6-3p%3C=0%29%7D%7D%0D%0A%7B%7B%7B12-3p%3C=0%29%7D%7D%0D%0A%7B%7B%7B12%3C=3p%29%7D%7D%0D%0A%7B%7B%7B12%2F3%3C=p%29%7D%7D%0D%0A%7B%7B%7Bhighlight%28p%3E=4%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The object be placed at most <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%284cm%29 ALIGN=MIDDLE  ALT=\"highlight%284cm%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > from the lens for its image to appear at least three times as large. </SPAN>\n" );
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