How do you simplify (4-3sqrt2)^2?

1 Answer
Sep 17, 2015

The answer is 2(17-12sqrt(2))

Explanation:

Use the formula (a-b)^2=a^2+b^2-2ab, to get

(4-3sqrt(2))^2= 4^2 + (3sqrt(2))^2 - 2*4*3sqrt(2).

4^2 is, of course, 16.

(3sqrt(2))^2 equals 3^2 * (sqrt(2))^2, which is 9*2=18.

As for the last term, you simply multiply the factors outside the square root: 2*4*3sqrt(2)=24sqrt(2).

Summing everything up, you have 16+18-24sqrt(2)=34-24sqrt(2), which you can further simplify into 2(17-12sqrt(2)).