Tolong dengan cara kerja kalau bisa difoto
Matematika
DendyRaglan
Pertanyaan
Tolong dengan cara kerja kalau bisa difoto
1 Jawaban
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1. Jawaban ahreumlim
1. f(x) = 2x - 5
g(x) = 3x² + 5
(fog)(x) = f(g(x))
= 2(3x² + 5) - 5
= 6x² + 10 - 5
= 6x² + 5
(gof)(x) = g(f(x))
= 3(2x - 5)² + 5
= 3(4x² - 20x + 25) + 5
= 12x² - 60x + 75 + 5
= 12x² - 60x + 80
2.
g(x) = (x+3) / (x-2)
y = (x+3) / (x-2)
y(x-2) = x + 3
xy - 2y = x + 3
xy - x = 2y + 3
x(y-1) = 2y + 3
x = (2y + 3) / (y - 1)
jadi g⁻¹(x) = (2x + 3) / (x - 1)
g(x) = √(x - 5)
y = √(x - 5)
y² = x - 5
x = y² + 5
Jadi g⁻¹(x) = x² + 5
f(x) = x² + 2x + 3
u/ x > -b/2a, maka
f⁻¹(x) = (-b + √(b² - 4a(c-x))) / 2a
= (-2 + √(2² - 4(3-x))) / 2
= (-2 + √4(1-3+x)) / 2
= (-2 + 2√(x-2)) / 2
= -1 + √(x-2)
u/ x < -b/2a, maka
f⁻¹(x) = (-b - √(b² - 4a(c-x))) / 2a
= (-2 - √(2² - 4(3-x))) / 2
= (-2 - √4(1-3+x)) / 2
= (-2 - 2√(x-2)) / 2
= -1 - √(x-2)