已知角α终边上的一点p(-4,3) cos(π/2+α)sin(-π-α)/cos(11π/2-α)sin(9π/2+α)

问题描述:

已知角α终边上的一点p(-4,3) cos(π/2+α)sin(-π-α)/cos(11π/2-α)sin(9π/2+α)

cos(π/2+α)sin(-π-α)/cos(11π/2-α)sin(9π/2+α)
=-sina*sina/(-sina)cosa
=tana
tana=/4/3
cos(π/2+α)sin(-π-α)/cos(11π/2-α)sin(9π/2+α)=-4/3