Question

(2+root) (2_ root 2 rational or irrational numbers ​

Answer 1

Answer:

rational number

Step-by-step explanation:

$given \\ (2 + \sqrt{2})(2 - \sqrt{2}) \\ we \: know \: that \\ x {}^{2} - y {}^{2} = (x + y)(x - y) \\ hence \:(2 + \sqrt{2} )(2 - \sqrt{2}) = (2) {}^{2} - ( \sqrt{2}) {}^{2} \\ = 4 - 2 = 2 \\ hence \: 2 \: is \: a \: rational \: number$

Answer 2

Answer:

$(2 + \sqrt{2} )(2 - \sqrt{2} )$

$= 4 - 2 \sqrt{2} + 2 \sqrt{2} - 2$

$= 4 - 2$

$= 2$