Let v be a velocity, t a time, x and r lengths. Let [A]=L (length)

Find the mks units of B and C for:

$\displaystyle r=\sqrt{Ax+Bt}C^2v$

What I found was that [A] could be length, B could be $\displaystyle \frac{L^2}{T}$ and C could be the square root of a time over the square root of a lengh times the fourth root of 2. My question is whether or not the 1 over 4th root of 2 is acceptable.