Ada yg bisa gk, tolong yaa pliiis ​

Jawaban:

fungsi invers

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14). f(x) = 7^(x – 3) , f^-1(343)

misal :

y = 7^(x – 3)

(x – 3) = ⁷log y

x = 3 + ⁷log y

f^-1(x) = 3 + ⁷log x

maka,

f^-1(343) = 3 + ⁷log 343

f^-1(343) = 3 + ⁷log 7³

f^-1(343) = 3 + 3

f^-1(343) = 6 (D)

15). f(x + 8) = x/5 + 4

misal :

y = x + 8

x + 8 = y

x = y – 8

f^-1(x) = x – 8

f(x) = x/5 + 4

f(x) = (x – 8)/5 + 4

f(x) = ((x – 8) + 20))/5

f(x) = (x + 12)/5

5y = x + 12

x + 12 = 5y

x = 5y – 12

f^-1(x) = 5x – 12

f^-1(3) = 5(3) – 12 = 15 – 12 = 3 (E)