document.write( "Question 220645: Find the exact value of tan 15 degrees \n" ); document.write( "
Algebra.Com's Answer #165586 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! Find the exact value of tan 15 \n" ); document.write( "------------------ \n" ); document.write( "[tan(15) = tan(60-45) \n" ); document.write( "= [tan(60)-tan(45)]/[1+tan(60)*tan(45)] \n" ); document.write( "--- \n" ); document.write( "= [sqrt(3)-1]/[1+sqrt(3)*1] \n" ); document.write( "Multiply numerator and denominator by 1-sqrt(3) to get: \n" ); document.write( "--- \n" ); document.write( "= [-(1-sqrt(3))^2]/(1-3) \n" ); document.write( "--- \n" ); document.write( "= (1-2sqrt(3)+3)/2 \n" ); document.write( "= (4-2sqrt(3)]/2 \n" ); document.write( "= (2-sqrt(3)) \n" ); document.write( "================== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |