For each pair of real numbers a \neq b, define the operation \star as
(a \star b)=\dfrac{a+b}{a-b}
What is the value of ((1 \star 2) \star 3) ?
Answer Choices
A. -\dfrac{2}{3}
B. -\dfrac{1}{5}
C. 0
D. \dfrac{1}{2}
E. This value is not defined.
For each pair of real numbers a \neq b, define the operation \star as
(a \star b)=\dfrac{a+b}{a-b}
What is the value of ((1 \star 2) \star 3) ?
Answer Choices
A. -\dfrac{2}{3}
B. -\dfrac{1}{5}
C. 0
D. \dfrac{1}{2}
E. This value is not defined.