sin^2α-2sinαcosα+2cosα^2=1/2 则tanα=

问题描述:

sin^2α-2sinαcosα+2cosα^2=1/2 则tanα=

sin²a-2sinacosa+2cos²a=(1/2)sin²a+(1/2)cos²asin²a-4sinacosa+3cos²a=0 【两边除以cos²a】tan²a-4tana+3=0(tana-3)(tana-1)=0则:tana=1或tana=3...