Akar-akar persamaan kuadrat 2x^2 – 3x + 5 = 0 adalah α dan β. nilai dari α/β + β/a = ….

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a. -12/10
b. – 11/10
c. -9/10
d. -7/10
e. – 3/10

mohon bantuannya ^^ dan terimakasih atas bantuannya 🙂

Akar-akar persamaan kuadrat 2x^2 – 3x + 5 = 0 adalah α dan β. nilai dari α/β + β/a = ….

2x² – 3x + 5 = 0 >> a=2, b=-3, c=5

α+β = -b/a
       = -(-3)/2
       = 3/2

α.β = c/a
      = 5/2

α/β + β/a = (α²+β²)/αβ
              = [(α+β)²-2αβ]/αβ
              = [(3/2)²-2(5/2)]/(5/2)
              = [(9/4)-5]/(5/2)
              = [(9/4)-(20/4)]/(5/2)
              = (-11/4)/(5/2)
              = -11/4 x 2/5
              = -11/10                       (b)