Question

I'll give medal to first answer.
Simplify:

square root of 3 times square root of 21

Answer 1

There's a couple of way s to do this.

√(3) * √(21) = √(3 * 21) = √(63)

But you can simplify this by looking at prime factors:

21 = 3*7
--> thus we could have written

√(3) * √(3*7) = √(3*3*7)

Since there are "two" 3's you can take the square root (because √(x*x) = x...or in this case √(3 * 3) = 3)

Thus this gives:

3 * √(7)

Answer 2

Thanks