Magnetic moment (μ)=n(n+2)
More than value of n, more will be magnetic moment.
Ti+2 electronic configuration;
3d2
μ=2(2+2)=2.82
Ti+3⇒3d1
μ=1(1+2)=3=1.73
V+2⇒3d3
μ=3(3+2)=3.87
Sc3+⇒[Ar] no unpaired electron. →μ=0
Hence Order of Magnetic Moment is V+2>Ti+2>Ti+3>Sc+3