Question

Can you check these two questions, please?
What is the product of 2 sqrt(u( sqrt(5)+ 3 sqrt(45))? Simplify if possible.

A) 20 sqrt(5)u
B) 20 sqrt(5)u + 9 sqrt(5)
C) 56 sqrt(5)u
D) 90u sqrt(5)

I think it's A.20 sqrt(5)u

Which expression is the simplified form of sqrt(k^21)?

A) k^5

B) k^10 sqrt(k)

C) k^10

D) k^4 sqrt(k)

Again, I think it's A. k^5

Answer 1

k^5 * k^5 = k^10

in other words
sqrt(k^10) = k^5

so it does not make sense that sqrt(k^21) also equals k^5