document.write( "Question 1064372: Given that cos θ = −16/65, θ in quadrant II, do the following.
\n" ); document.write( "(a) (4 pts) Draw the triangle for θ. Label.
\n" ); document.write( "(b) (4 pts each) Find exact values of sin 2θ, cos 2θ, and tan 2θ. No decimals.
\n" ); document.write( "(c) (2 pts) Determine the quadrant of 2θ. Justify your answer \n" ); document.write( "
Algebra.Com's Answer #679442 by ikleyn(52782)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "Given that cos θ = −16/65, θ in quadrant II, do the following.
\n" ); document.write( "(a) (4 pts) Draw the triangle for θ. Label.
\n" ); document.write( "(b) (4 pts each) Find exact values of sin 2θ, cos 2θ, and tan 2θ. No decimals.
\n" ); document.write( "(c) (2 pts) Determine the quadrant of 2θ. Justify your answer
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document.write( "a)  I will not do a). Instead, YOU do it.\r\n" );
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document.write( "b)  \"sin%28theta%29\" = \"sqrt%281-cos%5E2%28theta%29%29\" = \"sqrt%281+-+%28-16%2F65%29%5E2%29\" = \"63%2F65\". The sign at the square root is \"+\" since \"sin%28theta%29\" is positive in Q2.\r\n" );
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document.write( "    ====>  \"sin%282theta%29\" = \"2%2Asin%28theta%29%2Acos%28theta%29\" = \"2%2A%2863%2F65%29%2A%28-16%2F65%29\" = calculate.    ( Notice it is negative !)\r\n" );
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document.write( "           \"cos%282theta%29\" = \"2%2Acos%5E2%28theta%29-1\" = \"2%2A%28-16%2F65%29%5E2+-+1\" = calculate.     ( Notice it is negative !)\r\n" );
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document.write( "           \"tan%282theta%29\" = \"sin%282theta%29%2Fcos%282theta%29\" = calculate.\r\n" );
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document.write( "           For it, \"sin%282theta%29\" and \"cos%282theta%29\" you just calculated above  (I suppose !).\r\n" );
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document.write( "c)  Since both \"sin%282theta%29\" and \"cos%282theta%29\" are negative, the angle \"2theta\" is in Q3.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Completed.\r
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\n" ); document.write( "\n" ); document.write( "For more solved similar problems on calculating trig functions see the lessons \r
\n" ); document.write( "\n" ); document.write( "    - Calculating trigonometric functions of angles\r
\n" ); document.write( "\n" ); document.write( "    - Advanced problems on calculating trigonometric functions of angles\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Trigonometry: Solved problems\". \r
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