If x = √32 + √8, then what is the value of x²?
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Correct answer: A
Explanation
Given:
x = √32 + √8
According to the formula:
(a + b)² = a² + b² + 2ab
x² = (√32 + √8)²
= (√32)² + (√8)² + 2√32√8
= 32 + 8 + 2√(32 × 8)
= 40 + 2√256
= 40 + 2 × 16
= 40 + 32
= 72