Simplify the following please

Question

Simplify with No decimals please

 

1.

       √2

       ——

      5-√2

 

2.

    (5+√3) (2-√6)

 

 

3. 7√7 - 6√12 -(4√28 +4√3)

Answer 1

HINTS:

1.

Multiply both numerator and denominator with 5+√2, and use formula: a2 - b2 = (a+b)(a-b)

 

2.

√18 = √(9*2) = 3√2

 

3.

√12 = √(4*3) = 2√3

and

√28 = √(4*7) = 2√7