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Comments (4)
The function given is
y = 5^(log x)
We need the inverse, meaning we must rewrite it so that x is expressed in terms of y.
Step 1: Take log on both sides
log y = log(5^(log x))
Using the log rule
log(a^b) = b log a
So
log y = (log x)(log 5)
Step 2: Solve for log x
log x = (log y) / (log 5)
Step 3: Convert back from log form
If
log x = k
then
x = 10^k
x = 10^(log y / log 5)
Now use the identity
10^(log a / log b) = a^(1 / log b)
x = y^(1 / log 5)
x = y^(1 / log 5)
Therefore the inverse function is
That matches Option 3.
Original function raises 5 to a logarithmic power. When inverted, the variable moves into the base with a fractional exponent, which is why y gets raised to 1 / log 5.
Thankyou!
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