Question

simplify
1) (5+√7) (2+√5)
2) (5+√5) (5-√5)

$3)( \sqrt{3} -+ \sqrt{7} ) {}^{2}$
​

Answer 1

Answer:

20

Step-by-step explanation:

(5+√5) (5-√5)

= 5(5-√5) + √5(5-√5)

= (5×5) - 5√5 + 5√5 - (√5 - √5)

= 25 - 5√5 + 5√5 - 5

= 25 - 5

= 20

Hence (5+√5) (5-√5) = 20

Hope it is helpful.