f(x)=-7/x-9
What number must be excluded from the domain and why?
division by zero is undefined.
So, if x-9 is zero, it cannot be used as a divisor.
So, for what x is x-9 = 0?
Thank you Steve!
To determine the number that needs to be excluded from the domain of the function f(x) = -7/(x - 9), we need to identify any potential value of x that would result in undefined behavior.
In this case, the denominator of the function is x - 9. If x were to take a value that makes the denominator equal to zero, the function would become undefined because division by zero is undefined in mathematics.
To find the number that must be excluded from the domain, we solve the equation x - 9 = 0:
x - 9 = 0
x = 9
Therefore, the number that needs to be excluded from the domain of f(x) = -7/(x - 9) is x = 9. This is because the function would result in division by zero if x were equal to 9.