If x = 2 + √3, what is the value of x² − 4x + 1?
Correct answer C. 0
Explanation
x² = 4 + 4√3 + 3 = 7 + 4√3 and 4x = 8 + 4√3. So x² − 4x + 1 = 7 + 4√3 − 8 − 4√3 + 1 = 0.
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