In rectangular form z = a + ib:
z = i(sqrt 6 - sqrt 2 i) = √2 + i√6
In polar form z = r∠θ. First find r:
r = √(√2)2 + (√6)2) = √8 = 2√2
Now find θ:
θ = arctan(√6/√2) = arctan(√3) = 60°
Final polar form:
z = 2√2 ∠60°
You can use pi/3 in place of 60 degrees if you prefer radians.