Let \( f(x) = 2x^3 - 9ax^2 + 12a^2x + 1 \), where \( a > 0 \). The minimum of \( f \) is attained at a point \( q \) and the maximum is attained at a point \( p \). If \( p^3 = q \), then \( a \) is equal to:
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For cubic functions, critical points come from \( f'(x)=0 \). The smaller root gives maximum and larger gives minimum when leading coefficient is positive.