To simplify the logarithmic equation: `log_5(sqrt(x-4))=3.2` , recall the logarithm property: `a^((log_(a)(x))) = x` .
When a logarithm function is raised by the same base, the log cancels out which is what we need to do on the left side of the equation.
As a rule we apply same change on both sides of the equation.
Raising both sides by base of 5:
`5^(log_5(sqrt(x-4)))= 5^(3.2)`
`sqrt(x-4) = 5^(3.2)`
To cancel out the radical sign, square both sides:
`(sqrt(x-4))^2 = (5^(3.2)) ^2 `
`x-4 =5^(6.4)`
` x= 5^(6.4)+4`
` x~~29748.593` (rounded off to three decimal places)
To check, plug-in `x=29748.593` in `log_5(sqrt(x-4))` :
`log_5(sqrt(29748.593-4))`
`log_5(sqrt(29744.593))`
`log_5(172.4662083)=3.2` which is what we want
So, x=29748.593 is the real solution.
Note:` (x^m)^n= x^((m*n ))`
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