設(sinx)=2-cos2x,則f(cosπ/6)=?

設(sinx)=2-cos2x,則f(cosπ/6)=?

原式=f[sin(0/2-π/6)]
=f(sin(π/3))
=2-cos(2*π/3)
=2-(-1/2)
=5/2