Question

Find the product of (1+3√2) and (1-3√2). Is this product rational or irrational?​

Answer 1

$1 + 3 \sqrt{2 } \times 1 - 3 \sqrt{2} = {1}^{2} - {3 \sqrt{2} }^{2} = 1 - 18 = - 17$

Answer 2

Answer:

1-18=-17

so it is rational