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If one of the root of the quadratic equation is √ 5 - √3 ,



(vi) √ 5 - √3


Sol. If one of the root of the quadratic equation is √ 5 - √3 
 ,

then the other root is √ 5 + √3  

Let α= √ 5 - √3  and β= √ 5 + √3  

∴ α + β  = √ 5 - √3  + √ 5 + √3  = 2√5

and  α β  =  (√ 5 - √3  ) × (√ 5 + √3  )

= (√5)2  -  (√3)2

= 5 - 3

= 2

We know that, Quadratic equation is given by,

x2 – (Sum of the roots)x + Product of the roots = 0

∴ x2 –( α  + β)x + αβ = 0

∴ x2 – (2√5)x + (2) = 0

∴  x2 -  2√5x  + 2  = 0



∴  The required quadratic equation is  x2 -  2√5x  - 2  = 0