document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=898836>Question 898836</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use the trigonometric function values of the quadrant angles to evaluate.  <BR>\n" );
document.write( "7 cot 270 degrees + 3 cos 180 degrees. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #545020 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=545020\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 7*cot(270) = 0\r<BR>\n" );
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document.write( "3*cos(180) = -3\r<BR>\n" );
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document.write( "7*cot(270) - 3*cos(180) is equal to 0 + 3 which is equal to 3.\r<BR>\n" );
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document.write( "that's your solution.\r<BR>\n" );
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document.write( "i used a calculator.<BR>\n" );
document.write( "if i didn't have a calculator, i would do the following.\r<BR>\n" );
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document.write( "reference angle for 270 degrees is equal to 90 because 180 + 90 = 270.<BR>\n" );
document.write( "cot(90) = cos(90)/sin(90) = 0/1 = 0.<BR>\n" );
document.write( "cot(90) = 0<BR>\n" );
document.write( "270 is in between the third and fourth quadrant.<BR>\n" );
document.write( "since the cotangent is equal to 0, the sign doesn't matter, so cot(270) = 0.\r<BR>\n" );
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document.write( "reference angle for 180 is equal to 0 because 180 - 180 = 0.<BR>\n" );
document.write( "cos(0) = 1<BR>\n" );
document.write( "180 degrees is between second and third quadrant.<BR>\n" );
document.write( "cosine is negative when the angle is in between the second and third quadrant, so cos(180) = -1\r<BR>\n" );
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document.write( "therefore:\r<BR>\n" );
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document.write( "7*cot(270) - 3*cos(180) = 7*0 -  3*(-1) which is equal to 0 + 3 which is equal to 3.\r<BR>\n" );
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document.write( "the graphs of cot(270) and cos(180) are shown below:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src=\"http://theo.x10hosting.com/2014/090706.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src=\"http://theo.x10hosting.com/2014/090707.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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