Tính giá trị biểu thức sau

To simplify the expression, we first need to find a common denominator for the two fractions in the expression.

(1-√2)/(1+√2) = (1-√2)(1-√2)/(1+√2)(1-√2) = (1 - 2 - 2√2)/(1 - 2) = (-1 - 2√2)/(-1) = 1 + 2√2

(1+√2)/(1-√2) = (1+√2)(1+√2)/(1-√2)(1+√2) = (1 + 2 + 2√2)/(1 - 2) = (3 + 2√2)/(-1) = -3 - 2√2

Now, we can substitute these simplified fractions back into the original expression:

(1 + 2√2) - (-3 - 2√2) = 1 + 2√2 + 3 + 2√2 = 4 + 4√2

To simplify further, we can factor out a 4 from the expression:

4(1 + √2) = 4√72

Therefore, the simplified expression is 4√72.