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  1. If   x =
    3
    , then the value of
    1 + x + √1 − x
      is
    21 + x − √1 − x
    1. −√3
    2. –1
    3. 1
    4. 3
Correct Option: D

x =
3
1
=
2
2x3

By componendo and dividendo,
1 + x
=
2 + √3
1 − x2 − √3

⇒ 
1 + x
=
2 + √3
×
2 + √3
1 − x2 − √32 + √3

=
(2 + √3)2
=
(2 + √3)2
(2 − 3 √3)(2 + √3)4 − 3

⇒ 
1 + x
= (2 + √3)2
1 − x

∴ 
1 + x
=
2 + √3
1 − x1

By componendo and dividendo
1 + x + √1 − x
=
2 + √3 + 1
1 + x − √1 − x2 + √3 − 1

=
3 + √3
=
3( √3 + 1)
= √3
3 + 13 + 1



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