## The problem

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Hello? I keep getting wrong answer in this type of questions, so for example the answer here is 1/u-7 but the correct answer is just u=7

## Answer provided by our tutors

If the question is:

Find all excluded values for the expression.

Find all values of x for which the expression is undefined.

Then you need to put the denominator equaled to zero into the solver and solve for 'x':

And you will get the correct answer.

Click here to see the solution.