document.write( "Question 69491: Theta = x
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document.write( "If x is an acute angle with cos x = 1/9, find the exact value of sin a/2. \n" );
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Algebra.Com's Answer #49477 by Nate(3500)![]() ![]() ![]() You can put this solution on YOUR website! sin^2(0.5x) = 0.5(1 - cos(x)) \n" ); document.write( "sin^2(0.5x) = 0.5(1 - 1/9) \n" ); document.write( "sin^2(0.5x) = 0.5(8/9) \n" ); document.write( "sin^2(0.5x) = 4/9 \n" ); document.write( "sin(0.5x) = +- 2/3 \n" ); document.write( " |