document.write( "Question 740819: For the following, assume that all the given angles are in simplest form, so that if A is in QIV you may assume that 270° < A < 360°.\r
\n" );
document.write( "\n" );
document.write( "If sin B = − 1/5 with B in QIII, find the following.cot B/2
\n" );
document.write( " \n" );
document.write( "
Algebra.Com's Answer #451703 by stanbon(75887) ![]() You can put this solution on YOUR website! If sin B = − 1/5 with B in QIII, find the following. \n" ); document.write( "cot(B/2) = 1/tan(B/2) = (1 + sqrt(1+tan^2(B))/tan(B) \n" ); document.write( "----- \n" ); document.write( "Since sin(B) = -1/5, y = -1 and r = 5 \n" ); document.write( "Then x = sqrt(r^2-y^2) = sqrt(25-1) = sqrt(24) \n" ); document.write( "Note: x is negative in QIII \n" ); document.write( "So x = -sqrt(24) \n" ); document.write( "============ \n" ); document.write( "Therefore tan(B) = y/x = -1/-sqrt(24) = 1/sqrt(24) \n" ); document.write( "------------------------ \n" ); document.write( "Finally, cot(B/2) = (1 + sqrt(1+(1/24))/[1/sqrt(24)] \n" ); document.write( "--- \n" ); document.write( "= (1+sqrt(25/24))*(sqrt(24)) \n" ); document.write( "--- \n" ); document.write( "= (1+5/(sqrt(24))(sqrt(24) \n" ); document.write( "--- \n" ); document.write( "= sqrt(24)+5 \n" ); document.write( "====================== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H.\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |