Here, a1=√3, a2=2√3 and a3=3√3
a2−a1=2√3−√3=√3, a3−a2=3√3−2√3=√3
∵ a2−a1=a3−a2=√3=Common difference
Since the difference between successive terms are same, it forms an AP.
The next three terms are,
a4=a1+3d=√3+3(√3)=4√3
a5=a1+4d=√3+4√3=5√3
a6=a1+5d=√3+5√3=6√3