Question

How do you multiplying radical expression with different exponents `7^4sqrt(4a^3b) * 3sqrt(2a^2 b)`?

Answer 1

Note `sqrt(a) xx sqrt(b) = sqrt( a xx b)`
and `p sqrt(a) xx q sqrt(b) = pq sqrt(a xx b)`

So
`7^4 sqrt(4a^3b) * 3 sqrt(2a^2b)`
`= 3*7^4 sqrt(8a^5b^2)`
`=3*7^4*2a^2b sqrt(2a)`