A = { x ∈ N : x² < 64 } হলে, P(A) = ?

x = 1;
x³ = 1³ = 1

x = 2;
x³ = 2³ = 8

x = 3;
x³ = 3³ = 27

x = 4;
x³ = 4³ = 64 যা গ্রহণযোগ্য নয়।

অতএব,
A
= { x ∈ N : x³ < 64 }
= {1, 2, 3}

সুতরাং
P(A)
= {{1}, {2}, {3}, {1, 2}, {2, 3}, {3, 1}, {1, 2, 3}, Φ}
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প্রশ্নে ভুল রয়েছে।
প্রশ্নে A = { x ∈ N : x^3 < 64 } থাকলে উত্তর ঘ) {{1}, {2}, {3}, {1, 2}, {2, 3}, {3, 1}, A, Φ} ঠিক ছিলো।