Q14 of 51 Page 3

If x = and y =, then x + y + xy =

Given x = √5 +√3 / √5 - √3 , y =√5 - √3 / √5 + √3


X=


Y =


Xy = 42 - √152 = 16 – 15 = 1


So,


X + y+ xy = 4+√15 + 4 - √15 + 1 = 9.

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