mohon bantuan nya, mohoon banget, beberapa nomer juga gpp, soalnya tugas nya bsk di kumpulkan.... terimakasih....
Matematika
ziddan31
Pertanyaan
mohon bantuan nya, mohoon banget, beberapa nomer juga gpp, soalnya tugas nya bsk di kumpulkan....
terimakasih....
terimakasih....
1 Jawaban
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1. Jawaban Ashiela
1) f(x) = 4 / 2(3-x) = 2 / (3-x)
y = 2 / (3-x)
y(3-x) = 2
3y - xy = 2
3y - 2 = xy
x = (3y-2)/y
→ invers f(x) = (3x-2)/x
invers f(4) = (3.4-2)/4
= (12-2)/4 = 10/4 = 5/2
2) f(x) = 4x + 12
y = 4x + 12
y - 12 = 4x
x = ¼(y-12)
→ invers f(x) = ¼(x-12)
3) f(x) = 2x / (2x-2)
y = 2x / (2x-2)
y(2x-2) = 2x
2xy - 2y = 2x
2xy - 2x = 2y
x(2y-2) = 2y
x = 2y / (2y-2)
→ invers f(x) = 2x / (2x-2)
4) f(x) = 4x
g(x) = 6 - 10x
(g•f)(x) = 6 - 10(4x) = 6 - 40x
y = 6 - 40x
40x = 6 - y
x = (6-y)/40
→ invers (g•f)(x) = (6-x)/40
5) f^-1(x) = 6x + 3
g^-1(x) = x²
(f•g)^-1(x)
= (g^-1 • f^-1)(x)
= (6x + 3)² = 36x² + 36x + 9
6) g(x) = 6-10x
(g•f)(x) = 6-20x
6 - 10(f(x)) = 6 - 20x
6 - 6 + 20x = 10 (f(x))
20x = 10 (f(x))
f(x) = 20x/10 = 2x
7) f(x) = 4x²-6
f(f(x)) = f(4x²-6)
= 4(4x²-6)²-6
= 4(16x⁴-48x²+36)-6
= 64x⁴-192x²+144-6
= 64x⁴ - 192x² + 138
8) f(x) = 4x + 2x = 6x
g(x) = 2x²+2
h(x) = 4x
(h•g•f)(x)
= h(g(6x))
= h(2(6x)²+2)
= h(12x²+2)
= 4(12x²+2) = 48x²+8
9) f(x) = 4x
(f•g)(x) = -½x + 1
4 g(x) = -½x + 1
g(x) = ¼(-½x+1)
g(x) = -⅛x + ¼
10) f(x) = 8x
g(x) = 2 + 2x²
h(x) = 2x-4
(f•g•h)(x)
= f(g(2x-4))
= f(2 + (2+2x)²)
= 8(2 + (2+2x)²)
(f•g•h)(2)
= 8(2+ (2+2.2)²)
= 8 (2 + 6²)
= 8 (38) = 304