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  1. If a = 2 + √3 , then the value of
    a6 + a4 + a2 + 1
    is
    a3

    1. 45
    2. 65
    3. 42
    4. 56
Correct Option: D

a = 2 + √3

1
=
1
a2 + √3

1
=
( 2 - √3 )
a( 2 + √3 )( 2 - √3 )

1
=
2 - √3
= 2 - √3
a4 - 3

∴ a +
1
= 2 + √3 + 2 - √3 = 4
a

∴ Expression =
a6 + a4 + a2 + 1
a3

Expression = a3 + a +
1
+
1
aa3

Expression = a3 +
1
+ a +
1
a3a

Expression = a +
1
3 - 3a +
1
+ a +
1
aaa

Expression = a +
1
3 - 2a +
1
aa

Expression = (4)3 – 2 × 4 = 64 – 8 = 56



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