document.write( "Question 933382: Use the CAST rule to state the sign of each value. Check using calculator.\r
\n" ); document.write( "\n" ); document.write( "(a) tan 15 degrees
\n" ); document.write( "(b) sin 120 degrees
\n" ); document.write( "(c)cos 135 degrees
\n" ); document.write( "(d) tan(-15 degrees)
\n" ); document.write( "(e) sin(-45 degrees)\r
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Algebra.Com's Answer #566775 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
here is a pattern:\r
\n" ); document.write( "\n" ); document.write( "In the first quadrant (\"I\"), all ratios are \"positive\".\r
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\n" ); document.write( "\n" ); document.write( " In Quadrant \"II\", \"sin%28theta%29\" is positive, \"cos%28theta%29\" and \"tan+%28theta%29\" are negative.\r
\n" ); document.write( "\n" ); document.write( " In Quadrant \"III\", \"tan+%28theta%29\" is positive (both \"x\" and \"y\" are negative, so ​\"x%26%238203%3B%26%238203%3By%26%238203%3B%26%238203%3B\" is positive), \"sin%28theta%29\" and \"cos+%28theta%29\" are negative.\r
\n" ); document.write( "\n" ); document.write( " In Quadrant \"IV\", \"cos%28theta%29\" is positive, \"sin%28theta%29\" and \"tan%28theta%29\" are negative.\r
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\n" ); document.write( "\n" ); document.write( "Of course the reciprocal ratios, \"csc+%28theta%29\", \"sec%28theta%29\" and \"cot%28theta%29\" follow the same pattern:\r
\n" ); document.write( "\n" ); document.write( " In Quadrant \"II\", \"csc%28theta%29\" is positive, \"sec%28theta%29\" and \"cot%28theta%29\" are negative.\r
\n" ); document.write( "\n" ); document.write( " In Quadrant \"III\", \"cot%28theta%29\" is positive, \"csc%28theta%29\" and \"sec%28theta%29\" are negative.\r
\n" ); document.write( "\n" ); document.write( " In Quadrant \"IV\", \"sec%28theta%29\" is positive, \"csc%28theta%29\" and \"cot%28theta%29\" are negative.\r
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\n" ); document.write( "\n" ); document.write( "then, your answers will be:\r
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\n" ); document.write( "\n" ); document.write( "(a) \"tan%2815%29\" degrees ->In the first quadrant (\"I\"), all ratios are \"positive\".\r
\n" ); document.write( "\n" ); document.write( "(a) \"tan%2815%29=2-sqrt%283%29=0.268\"\r
\n" ); document.write( "\n" ); document.write( "(b) \"sin%28120%29\" degrees ->In Quadrant \"II\" \"sin%28theta%29\" is \"positive\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%28120%29=sqrt%283%29%2F2=0.866\"\r
\n" ); document.write( "\n" ); document.write( "(c)\"cos%28135%29\" degrees->In Quadrant \"II\"\"+cos%28theta%29\" is \"negative\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%28135%29=-1%2Fsqrt%282%29=-0.707\"\r
\n" ); document.write( "\n" ); document.write( "(d) \"tan%28-15%29\" degrees -> In Quadrant \"IV\" \"tan%28theta%29\" is \"negative\"\r
\n" ); document.write( "\n" ); document.write( "\"tan%28-15%29=sqrt%283%29-2=-0.268\"\r
\n" ); document.write( "\n" ); document.write( "(e) \"sin%28-45%29\" degrees ->In Quadrant \"IV\" \"sin%28theta%29\" is \"negative\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%28-45%29=-1%2Fsqrt%282%29=-0.707\"\r
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