问题
选择题
若tanθ+
|
答案
sin2θ=2sinθcosθ=
=2sinθcosθ sin2θ+cos2θ
=2tanθ tan2θ+1
=2 tanθ + 1 tanθ
=2 4 1 2
故选D．
搜题请搜索小程序“爱下问搜题”
若tanθ+
|
sin2θ=2sinθcosθ=
=2sinθcosθ sin2θ+cos2θ
=2tanθ tan2θ+1
=2 tanθ + 1 tanθ
=2 4 1 2
故选D．