document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=691294>Question 691294</A>: <I><SPAN STYLE=\"word-break: break-all;\"> VARIABLE STARS: Variable stars are ones whos brightness varies periodically. One of the most visible is R Leonis; its brightness is modeled by the function:\r<BR>\n" );
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document.write( "b(t) = 7.9 - 2.1COS (pie over 156)t NOTE: the pie over 156 both have t.\r<BR>\n" );
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document.write( "where t is measured in days.\r<BR>\n" );
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document.write( "A- find the period of R Leonis<BR>\n" );
document.write( "B- Find the maximum and minimum brightness<BR>\n" );
document.write( "C- graph the function b </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #426625 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=426625\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> VARIABLE STARS: Variable stars are ones whos brightness varies periodically. One of the most visible is R Leonis; its brightness is modeled by the function:\r<BR>\n" );
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document.write( "b(t) = 7.9 - 2.1COS (pie over 156)t NOTE: the pie over 156 both have t.\r<BR>\n" );
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document.write( "where t is measured in days.\r<BR>\n" );
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document.write( "A- find the period of R Leonis<BR>\n" );
document.write( "B- Find the maximum and minimum brightness<BR>\n" );
document.write( "C- graph the function b<BR>\n" );
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document.write( "1st, it's Pi, the Greek letter, not pie, the dessert.<BR>\n" );
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document.write( "b(t) = 7.9 - 2.1COS (pie over 156)t<BR>\n" );
document.write( "I think you mean:<BR>\n" );
document.write( "b(t) = 7.9 - 2.1cos(t*pi/156)<BR>\n" );
document.write( "A- find the period of R Leonis<BR>\n" );
document.write( "= 2pi/(pi/156) = 312 days<BR>\n" );
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document.write( "B- Find the maximum and minimum brightness<BR>\n" );
document.write( "Max = 7.9 - 2.1 = 5.8<BR>\n" );
document.write( "Min = 7/9 + 2.1 = 10<BR>\n" );
document.write( "(more negative numbers are brighter.  The sun =~ -27)<BR>\n" );
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document.write( "C- graph the function b\r<BR>\n" );
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document.write( " </SPAN>\n" );
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