document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1102568>Question 1102568</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ref # 1102550<BR>\n" );
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document.write( "cos(x) = 2<BR>\n" );
document.write( "Solve for x.<BR>\n" );
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document.write( "As an example from my book:<BR>\n" );
document.write( "cos(+/-arctan(2sqrt(6)/5) - i*ln(7) + n*2pi) = 10<BR>\n" );
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document.write( "--> cos(x) = 10<BR>\n" );
document.write( "x = +/-arctan(2sqrt(6)/5) - i*ln(7) + n*2pi<BR>\n" );
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document.write( "If cos(x) = 10 has a solution,<BR>\n" );
document.write( "I think cos(x) = 2 does also.<BR>\n" );
document.write( "I solved that years ago, but I don't remember how to do it now.<BR>\n" );
document.write( "I will figure it out, with or without help.<BR>\n" );
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document.write( "Then I wonder about cos(x) = 2 + i ???\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 #717276 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=717276\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cos(x) = 2 + i<BR>\n" );
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document.write( "take the inverse cosine of both sides to eliminate the cosine from the left hand side.<BR>\n" );
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document.write( "x = 2 * &#960; * n(1) + cos^(-1)(2 + i) for n(1) element of Z<BR>\n" );
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document.write( "or x = 2 * &#960; * n(2) - cos^(-1)(2 + i) for n(2) element of Z<BR>\n" );
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document.write( "Z is the set of integers<BR>\n" );
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