New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    If a³ - b³ = (a - b)(a² + ab + b²), find a³ - b³

    when a = 10 and b = 4.
    A 728 Correct Answer Incorrect Answer
    B 684 Correct Answer Incorrect Answer
    C 700 Correct Answer Incorrect Answer
    D 936 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Using the formula: a³ - b³ = (a - b)(a² + ab + b²) Substituting values: a - b = 10 - 4 = 6 a² + ab + b² = 10² + 10 * 4 + 4² = 100 + 40 + 16 = 156 a³ - b³ = 6 * 156 = 936 Correct Answer: d)

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