The least positive solution of cotπ33sin2x=3 lies in
0,π6
π9,π6
π12,π9
π3,π2
cotπ33sin2x=3⇒ π33sin2x=nπ+π6,n∈Z⇒ sin2x=33n+32
for solution n= 0
⇒ sin2x=32⇒ 2x=π3⇒x=π6