the set {x:x∈r,x≠2/7} is the domain of which of the following functions?

A. V(x)=1/2x-7
B. U(x)1/7x+2
C. T(x)1/7x-2
D. Q(x)=1/2x-7

1 answer

To determine which function has the domain \({x : x \in \mathbb{R}, x \neq \frac{2}{7}}\), we should examine each option for any restrictions on the input \(x\).

  1. A. \(V(x) = \frac{1}{2x - 7}\)
    The function is undefined when the denominator is zero: \[ 2x - 7 = 0 \implies 2x = 7 \implies x = \frac{7}{2} \] Hence, the domain is all real numbers except \(x = \frac{7}{2}\).

  2. B. \(U(x) = \frac{1}{7x + 2}\)
    This function is undefined when the denominator is zero: \[ 7x + 2 = 0 \implies 7x = -2 \implies x = -\frac{2}{7} \] Thus, the domain is all real numbers except \(x = -\frac{2}{7}\).

  3. C. \(T(x) = \frac{1}{7x - 2}\)
    This function is undefined when the denominator is zero: \[ 7x - 2 = 0 \implies 7x = 2 \implies x = \frac{2}{7} \] Therefore, the domain is all real numbers except \(x = \frac{2}{7}\).

  4. D. \(Q(x) = \frac{1}{2x - 7}\)
    Similar to option A, this function is undefined when the denominator is zero: \[ 2x - 7 = 0 \implies 2x = 7 \implies x = \frac{7}{2} \] Thus, the domain is all real numbers except \(x = \frac{7}{2}\).

The only function from the options provided that has the specified domain \({x : x \in \mathbb{R}, x \neq \frac{2}{7}}\) is:

C. \(T(x) = \frac{1}{7x - 2}\).