6.(2023•广东模拟)已知θ∈(π4,π2)\theta \in ({\frac{\pi }{4},\frac{\pi }{2}})θ∈(4π,2π),且sin2θ=53\sin 2\theta =\frac{\sqrt{5}}{3}sin2θ=35,则tanθ=(\tan \theta =(tanθ=( )))