(a + 4 + 2√2)(a + 4 - 2√2) = ?

1 answer

Using the FOIL method, we can expand the given expression:

(a + 4 + 2√2)(a + 4 - 2√2)

= a(a) + a(4) + a(-2√2) + 4(a) + 4(4) + 4(-2√2) + 2√2(a) + 2√2(4) + 2√2(-2√2)

= a^2 + 4a - 2√2a + 4a + 16 - 8√2 + 2√2a + 8√2 - 8

= a^2 + 4a + 4a + 16 - 8 - 2√2a + 2√2a + 8√2 - 8

= a^2 + 8a + 8

Therefore, (a + 4 + 2√2)(a + 4 - 2√2) = a^2 + 8a + 8.