Define the SI unit of length.

Explanation

Given `v=at^(2)+(b)/(c+t)`
The physical quantities which are having same dimensional formula only can be added .
Dimensional formula for `v=LT^(-1)`
Dimensional formula for `c=T`
Dimensional formula for `at^(2)=LT^(-1)`
`a=(LT^(-1))/(T^(2))=LT^(-3)`
Dimensional formula for `(b)/(c+t)=LT^(-1)`
`thereforeb=L[becausec+t=T]` .