Question

Diketahui g (x) = 3^x-¹, maka nilai g^-1(9)-g^-1(27)+g^-1(81)=​

Answer 1

Jawaban:

F(x) = 3^{x-1}

f^{-1}(x) = Invers dari f(x)

y = 3^{x-1}

log y = log 3^{x-1}

log 3^{x-1} = log y

x-1 log 3 = log y

x-1 = \frac{log y}{log 3}

x-1 = 3_{log} y

x = 3_{log} y + 1

x = 3_{log} y + 3_{log} 3

x = 3_{log} 3y

f^{-1}(x) = 3_{log } 3x atau

= 3_{log} x + 1