Question

1.diketahui fungsi f(x) = x-1 / 2-x. Hasil dari f-¹(x+1)...
2. jika f (x+1) = 2x+4 / x-2, maka nilai x yang memenuhi (fof)-¹(x) = 4x+3 adalah...
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Answer 1

1) f(x) = (x - 1) / (2 - x)

misalkan f(x) = y
y = (x - 1) / (2 - x)
y (2 - x) = x - 1
2y - xy = x - 1
2y + 1 = x + xy
2y + 1 = x(y + 1)
x = (2y + 1) / (y + 1)

f-¹(x) = (2x + 1) / (x + 1)
f-¹(x + 1) = (2(x + 1) + 1) / ((x + 1) + 1)
f-¹(x + 1) = (2x + 2 + 1) / (x + 2)
f-¹(x + 1) = (2x + 3) / (x + 2)