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If x = 3 + 2√2 , then the value of x6 + x4 + x2 + 1 is equal to x3
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- 216
- 192
- 198
- 204
- 216
Correct Option: D
| Expression = | ||
| x3 |
| Expression = | + | + | + | |||||
| x3 | x3 | x3 | x3 |
| Expression = x3 + x + | + | ||
| x | x3 |
| Expression = | ![]() | x3 + | ![]() | + | ![]() | x + | ![]() | |||
| x3 | x |
| Expression = | ![]() | x + | ![]() | 3 | - 3 | ![]() | x + | ![]() | + | ![]() | x + | ![]() | ||||
| x | x | x |
| Expression = | ![]() | x + | ![]() | 3 | - 2 | ![]() | x + | ![]() | ---(i) | ||
| x | x |
Now, x = 3 + 2√2
| ∴ | = | ||
| x | 3 + 2√2 |
| = | × | ||
| 3 + 2√2 | 3 - 2√2 |
| = | |||
| x | 9 - 8 |
| ∴ x + | = 3 + 2√2 + 3 - 2√2 = 6 | |
| x |
∴ Expression = (6)3 - 2 × 6 = 216 –12 = 204

