Find the value of ccc such that ⟨c,3c⟩\langle c, 3c \rangle⟨c,3c⟩ is a unit vector.
c=110c = \frac{1}{\sqrt{10}}c=101
c=110c = \frac{1}{10}c=101
c=14c = \frac{1}{4}c=41
c=12c = \frac{1}{2}c=21