document.write( "Question 170144: I'm attempting to do corrections on a test, but these three questions are giving me trouble! I've tried several different things, and I keep coming up with the same (wrong!) answer!\r
\n" ); document.write( "\n" ); document.write( "1) If \"x\" is an angle in quadrant 4 and \"Cot%28x%29=+-7%2F24\", find the value of \"Sin\"\"1%2F2\"\"x\".\r
\n" ); document.write( "\n" ); document.write( "2) What is the solution set of the equation\r
\n" ); document.write( "\n" ); document.write( " \"Sin%282x%29+-+Cos%5E2x%2B1+\" = \"+Sin%5E2x%2B+Sin%28x%29+\" in the interval \"0%3C=x%3C2pi\"?\r
\n" ); document.write( "\n" ); document.write( "3) Find the solution set of \"6Sin%28x%29+%2B+11=+2Csc%28x%29\" over the domain \"0%3Cx%3C360\"°.
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Algebra.Com's Answer #125583 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
1) If x is an angle in quadrant 4 and cotx= -7/24, find the value of
\n" ); document.write( "sin[(1/2)x].
\n" ); document.write( "If cotx = -7/24, x = 7 and y = -24
\n" ); document.write( "Then r = sqrt(7^2 + 24^2) = 25
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\n" ); document.write( "sin[(1/2)x] = sqrt[(1-cos(x))/2]
\n" ); document.write( "So, sin[(1/2)x] = sqrt[(1-(7/25))/2] = sqrt[9/25] = 3/5
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\n" ); document.write( "\n" ); document.write( "2) What is the solution set of the equation sin(2x)-cos^2(x+1) = sin^2(x)+sinx in the interval 0\n" ); document.write( "Comment: That is a mess to analyze. Graph the left side and the right side
\n" ); document.write( "separagely and see where they intersect under the condition the 0\n" ); document.write( "=============================================================\r
\n" ); document.write( "\n" ); document.write( "3) Find the solution set of 6sinx + 11= 2cscx over the domain 0\n" ); document.write( "Multiply thru by sin(x) to get:
\n" ); document.write( "6sin^2(x) + 11sin(x) - 2 = 0
\n" ); document.write( "---
\n" ); document.write( "Let w = sin(x)
\n" ); document.write( "Substitute to get:
\n" ); document.write( "6w^2 + 11w - 2 = 0
\n" ); document.write( "6w^2 +12w - w -2= 0
\n" ); document.write( "6w(w+2) -(w+2) = 0
\n" ); document.write( "(w+2)(6w-1) = 0
\n" ); document.write( "w = -2 or w = 1/6
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\n" ); document.write( "Solve for x:
\n" ); document.write( "sin(x) = -2 or sin(x)= 1/6
\n" ); document.write( "sin(x) cannot be -2.
\n" ); document.write( "If sin(x) = 1/6, x = 9.594.. degrees or 170.41 degrees
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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