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  1. If x = 3 + 2√2 , then the value of
    x6 + x4 + x2 + 1
    is equal to
    x3

    1. 216
    2. 192
    3. 198
    4. 204
Correct Option: D

Expression =
x6 + x4 + x2 + 1
x3

Expression =
x6
+
x4
+
x2
+
1
x3x3x3x3

Expression = x3 + x +
1
+
1
xx3

Expression = x3 +
1
+ x +
1
x3x

Expression = x +
1
3 - 3x +
1
+ x +
1
xxx

Expression = x +
1
3 - 2 x +
1
---(i)
xx

Now, x = 3 + 2√2
1
=
1
x3 + 2√2

=
1
×
3 - 2√2
3 + 2√23 - 2√2

1
=
3 - 2√2
x9 - 8

∴ x +
1
= 3 + 2√2 + 3 - 2√2 = 6
x

∴ Expression = (6)3 - 2 × 6 = 216 –12 = 204



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