Question

What value(s) of x is/are not allowed for the following rational expressions?

Please include the solutions. ​

Answer 1

We are given the fractions.

As we know the denominator of a fraction can't be zero.

So the values of x that are not allowed are:

• 1. x - 1 ≠ 0 ⇒ x ≠ 1
• 2. x(x + 6) ≠ 0 ⇒ x ≠ 0 and x + 6 ≠ 0⇒ x ≠ -6
• 3. (x + 2)(x + 8) ≠ 0 ⇒ x ≠ -2 and x ≠ -8
• 4. x + √7 ≠ 0 ⇒ x ≠ -√7
• 5. (x - 15)(x + 1) ≠ 0 ⇒ x ≠ 15 and x ≠ -1