document.write( "Question 867861: what is the exact value of sin 900 degrees \n" ); document.write( "
Algebra.Com's Answer #523256 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "I wish the other tutors would EXPLAIN HOW and WHY they \r\n" );
document.write( "get their answers instead of just stating answers.\r\n" );
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document.write( "Here is an explanation as to how and why the other tutor \r\n" );
document.write( "just blurted out:\r\n" );
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document.write( "sin(900°) = 0  with no explanation.\r\n" );
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document.write( "Let's find an angle that is coterminal with 900° \r\n" );
document.write( "that is less than 360°.  We do a long division by 360°\r\n" );
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document.write( "      2\r\n" );
document.write( "360)900\r\n" );
document.write( "    720\r\n" );
document.write( "    180 \r\n" );
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document.write( "So we see that 900° is two complete revolutions and \r\n" );
document.write( "ends up coterminal with 180°,   Below is a picture of\r\n" );
document.write( "the angle 900°.  The curved arrow shows the rotation\r\n" );
document.write( "of 2 complete revolutions plus a remainder of 180°:\r\n" );
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document.write( "So we see that 900° has the same trig functions as 180°.\r\n" );
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document.write( "So \r\n" );
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document.write( "sin(900°) = sin(180°) = 0\r\n" );
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document.write( "and  it you had been asked for the cosine\r\n" );
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document.write( "cos(900°) = cos(900°) = -1.\r\n" );
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document.write( "That is WHY sin(900°) = 0, and cos(900°) = -1.\r\n" );
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document.write( "Edwin
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