第一步:设log(1/2)sin π/12=X,则有拍埋1/2^X=sin π/122^X=4^X*sin π/12故 log(1/2)sin π/12=log2sin (π/12)*4^log(1/2)sin π/12第二步神贺租:log2sin (π/12)*4^log(1/2)sin π/12—log2cos π/12=4^log(1/2)sin π/游兆12*tan π/12