Question

Marta solved a logarithmic equation. Her work is shown.

Select the correct answer from each drop-down menu to complete the statements about Marta’s solution.

Answer 1

Explanation:

You are correct. Whenever you are dealing with equation that have functions in them, you must know their domain restrictions before you simplify.

For instance the function

`- 2 log_(5)(x)`

mUST be defined when x is non negative so that why -1 does not work as a solution. It is a extraneous solution.

Note that however if the function appeared as

`- 2 log_(5)( {x}^(2) )`

x=-1 would be a valid solution. However, we go off the original function for cases like this.