document.write( "Question 47978: can someone help me with the following i'm kind of lost at what to do. thanks!!\r
\n" ); document.write( "\n" ); document.write( "\"Evaluate the following expressions:\"
\n" ); document.write( "a.) $\"cot%28-pi%2F2%29\"$
\n" ); document.write( "b.) $\"sin%5E2%285pi%2F6%29\"$ ...(note) that is sin^2
\n" ); document.write( "c.) $\"sec%5E2%2811pi%2F6%29\"$ ...(note) that is sec^2
\n" ); document.write( "d.) $\"sec%5E-1%28sec%28-30degrees%29%29\"$ is finding out an angel first of all\r
\n" ); document.write( "\n" ); document.write( "i know that i have to use the unit circle but i dont know what to do.
\n" ); document.write( "any help would help thanks!!! \n" ); document.write( "

Algebra.Com's Answer #31757 by ChillyWiz282(3) $\"\"$ $\"About$

You can put this solution on YOUR website!
1. cot, $\"cot%28-pi%2F2%29=%28cos%28-pi%2F2%29%2Fsin%28-pi%2F2%29%29\"$ , $\"cos%28-pi%2F2%29=0\"$ , $\"sin%28-pi%2F2%29=-1\"$ , then $\"cot%28-pi%2F2%29=+0\"$
\n" ); document.write( "2. $\"sin%285pi%2F6%29\"$ has a reference angle of $\"pi%2F6\"$ } and in Quadrant 2. sin is negative in Quadrant 2. $\"sin%28pi%2F6%29=1%2F2\"$ , so $\"sin%285pi%2F6%29=-1%2F2\"$ .
\n" ); document.write( "Take the square of $\"%28-1%2F2%29%5E2\"$ gives us 1/4
\n" ); document.write( "3. $\"Sec%2811pi%2F6%29\"$ has a reference angle of $\"pi%2F6\"$ and in Quadrant 4. Sec is positive in Quadrant 4. $\"sec%28pi%2F6%29=1%2Fcos%28pi%2F6%29\"$ and $\"cos%28pi%2F6%29=%28sqrt%283%29%29%2F2\"$ then $\"sec%28pi%2F6%29=2%2F%28sqrt%283%29%29\"$
\n" ); document.write( "Squaring it gives $\"%282%2F%28sqrt%283%29%29%29%5E2=4%2F3\"$
\n" ); document.write( "4. $\"sec%5E-1%28sec%28-30degrees%29%29=+30++or+-30+degree\"$
\n" ); document.write( " $\"sec%28-30degree%29=+2%2F%28sqrt%283%29%29\"$
\n" ); document.write( " $\"sec%5E-1%282%2F%28sqrt%283%29%29%29=+30++or+-30+degree\"$
\n" ); document.write( "since in both Quadrant 1 and 4, sec(-30degree) is positive \n" ); document.write( "

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