If Tanθ+Secθ=3, then the principal value of θ+π6 is
π3
π4
2π3
π2
tanθ+secθ=3⇒sinθ+1=3cosθ
⇒3cosθ−sinθ=1⇒32cosθ−12sinθ=12
⇒cosθcosπ6−sinθsinπ6=12⇒cosθ+π6=12
∴ PS of θ+π6=π3