document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=233584>Question 233584</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve : cos X + sin X = 0 <BR>\n" );
document.write( "all answers in radians<BR>\n" );
document.write( "thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #172404 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=172404\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cos(x) + sin(x) = 0\r<BR>\n" );
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document.write( "They have to be equal with opposite sign so they can cancel each other out.\r<BR>\n" );
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document.write( "When x = 45 degrees, sin(x) and cos(x) are the same = .707106781\r<BR>\n" );
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document.write( "That's because they're in the first quadrant and sin(x) and cos(x) are both positive because:\r<BR>\n" );
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document.write( "opposite = length of the line is always positive.<BR>\n" );
document.write( "adjacent is distance on the x-axis to the right of the y-axis and is positive.<BR>\n" );
document.write( "opposite is distance on the y-axis up from the x-axis and is positive.\r<BR>\n" );
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document.write( "Go to the second quadrant and form 45 degrees up from 180 degrees.<BR>\n" );
document.write( "hypotenuse is positive.<BR>\n" );
document.write( "adjacent is negative (left of y-axis)<BR>\n" );
document.write( "opposite is positive (up from x-axis)\r<BR>\n" );
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document.write( "the values are the same but now the sin(x) is positive and cos(x) is negative.\r<BR>\n" );
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document.write( "180 - 45 = 135 so we are talking about sin(135) and cos(135).\r<BR>\n" );
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document.write( "you get:\r<BR>\n" );
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document.write( "sin(135) + cos(135) = 0 because:\r<BR>\n" );
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document.write( ".707106781 - .707106781 = 0\r<BR>\n" );
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document.write( "Your answer is 135 degrees.\r<BR>\n" );
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