bantu jawab kak udah binggung soal
Jawaban:
nomor 2
[tex]3x {}^{2} + 13x + 4 = 0 \\ (3x + 12)(3x + 1) \\ x = - 12 \: atau \: x = - 1[/tex]
maka
[tex] \frac{1}{ - 12} + \frac{1}{ - 1} = \frac{1 + 12}{ - 12} = \frac{13}{ - 12} [/tex]
maaf kalo salah
Penjelasan dengan langkah-langkah:
nomor (2)
3x² + 13x + 4 = 0
a = 3 , b = 13 , c = 4
x1.x2 = c/a = 4/3
x1+x2 = -b/a = -13/3
Maka:
1/x1 + 1/x2 = (x1 + x2)/(x1.x2) = (-13/3)/(4/3) = -13/3 x 3/4 = -13/4
nomor (4)
fungsi kuadrat y = 1 - (5+x)(1 - x)
y = 1 - (5 - 5x + x - x²)
y = 1 - (5 - 4x - x²)
y = 1 - 5 + 4x + x²
y = x² + 4x - 4
.
a = 1 , b = 4, c = -4
.
Xp = -b/2a = -4/2(1) = -4/2= -2
.
Yp = -D/4a = -(b² -4ac)/4a = -(4² - 4(1)(-4))/4(1) = -(16 + 16)/(4) = -32/4 = -8
Koordinat titik balok fungsi adalah Xp, Yp = { -2 , -8 }
[answer.2.content]
