How do you simplify square roots?

Answer 1

Make use of the property that sqrt(ab)=sqrt(a) x sqrt(b) and try to find an 'a' or 'b' that can be expressed as a whole number; these combinations of a square root and a coefficient are called surds.

e.g. In square root form, sqrt(18) = sqrt(9 x 2)= sqrt(9) x sqrt(2). This, in surd form, is 3 x sqrt(2).

Note that the property sqrt(ab) = sqrt(a) X sqrt(b) does not hold for negative radicands (imaginary numbers) unless negative roots are accounted for. For example, it is known that sqrt(-1) X sqrt(-1) = -1. The property mentioned above would imply that sqrt(-1) X sqrt(-1) = sqrt(-1 X (-1) = sqrt(1) which is only true if the square root of 1 is taken to be either 1 or -1.

Answer 2

It might be best to answer this with an example. Look at the square root of 8. To simplify it we notice that 8 is 2x4 and that 4 is a perfect square. So we can simplify the square root by taking the 4 out of the radical sign and writing it as 2xsquare root of 2. Perhaps a better way to think of this is that is you have square root of a x square root of b, that is the square root of (ab). So if we have square root of 8 that is the same as square root of 4 x square root of 2 and square root of 4 is 2 so the answer is 2xsquare root of 2. In general, look for perfect squares and factor them out of the number so they can be removed from the square root.

Answer 3

you cant simplify a square root