Question

Simplify as far as possible without a calculator.
(7+2√2)(7−2√2)

Answer 1

41

Explanation:

Given

(7 + 2
`√(2)` )(7 - 2
`√(2)` ) ← expand factors using FOIL

= 7² - 2
`√(2)` + 2
`√(2)` - (2
`√(2)` )² ← collect like terms

= 49 - 8

= 41