document.write( "Question 551241: Indicate whether each of the following is true or false.
\n" ); document.write( "sin 25° = sin 155°
\n" ); document.write( "tan 20° = cot 70°
\n" ); document.write( "sinƟ = cos(90-Ɵ)
\n" ); document.write( "tanƟ = -cot(90-Ɵ)
\n" ); document.write( "sinƟ = 1/cscƟ, where sinƟ is not 0
\n" ); document.write( "cosƟ = 1/secƟ, where cosƟ is not 0
\n" ); document.write( "sinƟ is never greater than 1 or less than -1
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Algebra.Com's Answer #359561 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
sin 25° = sin155°
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document.write( "155° is in the 2nd quadrant, and has a reference angle of 180°-155° = 25°\r\n" );
document.write( "and the sine is positive in both the 1st and 2nd quadrants.  So the answer is\r\n" );
document.write( "yes\r\n" );
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\n" ); document.write( "tan 20° = cot 70°
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document.write( "Yes because \r\n" );
document.write( "1. cotangent and tangent are cofunctions of each other, \r\n" );
document.write( "2. Co-functions of complementary angles are equal.\r\n" );
document.write( "3. 20° and 70° are complementary because their sum is 90°\r\n" );
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\n" ); document.write( "sinƟ = cos(90-Ɵ)
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document.write( "Yes, because\r\n" );
document.write( "1. cosine and sine are cofunctions of each other, \r\n" );
document.write( "2. Co-functions of complementary angles are equal.\r\n" );
document.write( "3. Ɵ° and 90°-Ɵ are complementary because their sum is 90°\r\n" );
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\n" ); document.write( "tanƟ = -cot(90-Ɵ)
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document.write( "No, because\r\n" );
document.write( "1. cotangent and tangent are cofunctions of each other, \r\n" );
document.write( "2. Ɵ° and 90°-Ɵ are complementary because their sum is 90°\r\n" );
document.write( "3. Co-functions of complementary angles are equal, so one \r\n" );
document.write( "cannot have the opposite sign from the other!\r\n" );
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\n" ); document.write( "sinƟ = 1/cscƟ, where sinƟ is not 0
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document.write( "Yes, because sine and cosecant are reciprocal trig functions.\r\n" );
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\n" ); document.write( "cosƟ = 1/secƟ, where cosƟ is not 0
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document.write( "Yes, because cosine and secant are reciprocal trig functions.\r\n" );
document.write( "

\n" ); document.write( "sinƟ is never greater than 1 or less than -1
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document.write( "True because the sine is \"opposite%2Fhypotenuse\" and the opposite is\r\n" );
document.write( "never greater than the hypotenuse.\r\n" );
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document.write( "Edwin
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