document.write( "Question 198049: Find the value of the five other trig functions, given sinx=square root -2/2 and cosx<0 also give degree and radian measure of x \n" ); document.write( "

Algebra.Com's Answer #148908 by Edwin McCravy(20063) $\"\"$ $\"About$

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Find the value of the five other trig functions, given \r
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document.write( "I will use a capital X to represent the angle, and a \r\n" );
document.write( "small x to represent the x-coordinate in the graph.\r\n" );
document.write( "Don't get them confused!\r\n" );
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document.write( "Since\r\n" );
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document.write( "and that is a negative number, this tells us that \r\n" );
document.write( "the angle X is in either QIII of QIV.\r\n" );
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document.write( "Since\r\n" );
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document.write( "that tells us that the cosine is a negative number,\r\n" );
document.write( "and we know that the cosine is negative in QII and QIII,\r\n" );
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document.write( "so therefore we know that angle X is in QIII, so we\r\n" );
document.write( "draw it:\r\n" );
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document.write( "Since the sine is , we take the\r\n" );
document.write( "numerator of the given sine, which is  to be the \r\n" );
document.write( "value of y, and the denominator 2 to be the value of r.\r\n" );
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document.write( "Next we calculate the value of x (small x) using the Pythagorean\r\n" );
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document.write( "We know to take the velue of x as negative, because\r\n" );
document.write( "x goes left from the origin, so\r\n" );
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document.write( "and we label it thusly:\r\n" );
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document.write( "Now we get the other 5 trigonometric functions by using\r\n" );
document.write( "the definitions:\r\n" );
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document.write( "Since the right triangle has two legs equal it is isosceles\r\n" );
document.write( "are the reference angle is therefore 45°.\r\n" );
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document.write( "Since the angle is in QIII, we must add 180° to its\r\n" );
document.write( "reference angle, so\r\n" );
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document.write( "the angle X in degree measure is 45°+180° or 225°\r\n" );
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document.write( "In radian measure, we multiply by \r\n" );
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document.write( "Edwin

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