A Nice Algebra Problem | Math Olympiad | Equation

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  • เผยแพร่เมื่อ 4 พ.ย. 2024

ความคิดเห็น • 16

  • @quinty.support
    @quinty.support วันที่ผ่านมา +1

    a + b = ab = a/b
    (•°•) a + b = ab
    ab = a/b
    a + b = a/b
    By the equation: a + b = a/b
    Multiply both sides by b.....
    b(a + b) = b • a/b
    => ab + b² = a - (1)
    Substitute the value of a by (1) in the other equation:
    a + b = ab
    => (ab + b²) + b = ab
    => ab + b² + b - ab = 0 [Cancel → ab from both sides]
    => b² + b = 0
    => b(b + 1) = 0
    So either.....
    b = 0 or b + 1 = 0
    since b is in the denominator of (a/b) it is a non zero so first case → [rejected]
    b + 1 = 0
    => b = -1
    When b = -1, a + b = ab
    => a - 1 = -a
    [Add → +a on both sides of LHS and RHS]
    => a - 1 + a = 0
    => 2a - 1 = 0
    => 2a = 1
    => a = 1/2
    Verifying this value:
    a = 1/2, b = -1
    a + b = ab
    1/2 - 1 = 1/2
    => 1/2 = 1/2 [Verified]
    Since all the equations are same and equal... verification in one is true for all....
    hence, a = 1/2 ; b = -1 is the solution that satisfies all equation...

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +1

      Very nice! ❤

  • @MananArhamOP
    @MananArhamOP วันที่ผ่านมา +1

    Big fan

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +1

      Thank you so much! ❤

  • @key_board_x
    @key_board_x 15 ชั่วโมงที่ผ่านมา +1

    ab = a/b → where: b ≠ 0
    ab - (a/b) = 0
    (ab² - a)/b = 0
    ab² - a = 0
    a.(b² - 1) = 0
    First case: a = 0
    Given: a + b = a/b → when: a = 0
    0 + b = 0/b
    b = 0 → rejected because the condition: b ≠ 0
    Second case: (b² - 1) = 0
    b² = 1
    b = ± 1
    First solution: b = 1
    Given: a + b = a/b → when: b = 1
    a + 1 = a/1
    a + 1 = a
    1 = 0 ← false, solution to be rejected
    Second solution: b = - 1
    Given: a + b = a/b → where: b = - 1
    a - 1 = a/- 1
    a - 1 = - a
    2a = 1
    a = 1/2
    Unique solution (a ; b) → (1/2 ; - 1)

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +1

      Very nice! ❤

  • @tingsuji8331
    @tingsuji8331 วันที่ผ่านมา +1

    Very interesting 😊

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +1

      Glad you think so! ❤

  • @9허공
    @9허공 วันที่ผ่านมา +1

    let a/b = k => a = bk, ab = k => kb^2 = k =>k(b^2 - 1) = 0 => k = 0 or b = 1, -1
    (case k = 0) => a = 0, b = 0 => since b ≠ 0, no solution.
    (case b = 1) => a + 1 = a = a/1 => no solution.
    (case b = -1) => a - 1 = -a = a/-1 => a =1/2 Answer (a,b) = (1/2, -1)

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +2

      Very nice! ❤

  • @trojanleo123
    @trojanleo123 12 ชั่วโมงที่ผ่านมา

    a = 1/2 ; b = -1

  • @mkadx2136
    @mkadx2136 วันที่ผ่านมา +1

    تستطيع حلها عن طريق التمثيل الباتي في اقل من دقيقة

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +2

      لطيف جدًا❤

  • @shmuelzehavi4940
    @shmuelzehavi4940 3 ชั่วโมงที่ผ่านมา

    You've already showed that a=0 implies: b=0, which is impossible at first place. This fact excludes the solution: a=0. Therefore, it is logically pointless to put afterwards the value : a=0 into the other equations.

  • @clayton97330
    @clayton97330 วันที่ผ่านมา +3

    As soon as a case is disproven by one equation, you don't need to check the other equations.

    • @SALogics
      @SALogics  13 ชั่วโมงที่ผ่านมา +1

      Very nice! ❤