Tolong ya nomor 24 dan 25 pakai cara yah, tnx
——24——
Diketahui :
– Persamaan Kuadrat => 2x² – 4x – 6 = 0
– a = 2
– b = – 4
– c = – 6
Ditanya :
– Nilai x₁² + x₂² = …..?
Penyelesaian :
– Nilai x₁² + x₂² :
x₁² + x₂²
= (x₁ + x₂)² – 2x₁x₂
= (- b/a)² – 2(c/a)
= (4/2)² – 2(- 6/2)
= 2² – 2(- 3)
= 4 – (- 6)
= 4 + 6
= 10
Jawaban : C. 10
——25——
Diketahui :
– Persamaan Kuadrat => 2x² – 6x + p = 0
– a = 2
– b = – 6
– c = p
– x₁x₂ = 1/2
Ditanya :
– Nilai p = …..?
Penyelesaian :
– Nilai p :
x₁x₂ = 1/2
c/a = 1/2
p/2 = 1/2
p = 1
Jawaban : A. 1
Sorry Kalau Salah