Question

(5+✓5) (5-✓5) following expression
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Answer 1

Formula to be used :-

(a+b) (a-b)

= a² - b²

(5+√5)(5-√5)

= 5² - √5²

= 25 - 5

= 20

Answer 2

Answer:

We know that

(a + b)(a - b) = a^2 - b^2

So here,

• a = 5
• b = √5

So,

(5+✓5) (5-✓5) = 5^2 - √5^2

= 25 - 5

= 20