You can put this solution on YOUR website! We start with fourth root (49*u^14).
We can rewrite this in fractional exponent form as
(i)
Now, we are looking for groups of 4 in order to pull out one set. So I will expand (i) to get
(ii)
Now I look for groups of four. I get
(iii)
I see 3 groups of 4 u's, so I can take out the 3 groups as u^3. Nothing else comes out, so we are left with the answer as:
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