The value of f(-6) is -12.2
Explanation:
Given that the function 
We need to determine the value of f(-6)
The value of f(-6) can be determined by substituting the value for  in the function and simplify the function.
 in the function and simplify the function.
Hence, let us substitute  in the function, we get,
 in the function, we get,

Let us apply the rule  , we get,
 , we get,

Multiplying the numbers, we get,

The value of 
Substituting the value of  , we get,
 , we get,

Subtracting the denominator, we have,

Dividing, we have,

Rounding off to the nearest tenth, we have,

Thus, the value of f(-6) is -12.2