If (3 - √7)/(3 + √7) = a + b√7, then the values of a and b are, respectively:
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Correct answer: A
Explanation
(3 − √7)/(3 + √7) = a + b√7
= [(3 − √7) × (3 − √7)] / [(3 + √7)(3 − √7)]
= (9 + 7 − 6√7) / (9 − 7)
= (16 − 6√7) / 2
= 8 − 3√7
a + b√7 = 8 − 3√7
a = 8 and b = −3