Answer: The correct conclusion is(B) The functions f(x) and g(x) are reflections over the y-axis.
Step-by-step explanation: Two functions f(x) and g(x) are given as follows:
[tex]f(x)=2^x,~~~~~~~g(x)=\left(\dfrac{1}{2}\right)^x.[/tex]
We know that if f(-x) = g(x), then the functions are reflections over Y-axis and if - f(x) = g(x), then the functions are reflections over X-axis.
We have,
[tex]f(-x)=2^{-x}=\left(\dfrac{1}{2}\right)^x=g(x),\\\\-f(x)=-2^x\neq g(x).[/tex]
So, the function g(x) is a reflection of f(x) over Y-axis.
The graph of f(x) and g(x) are drawn in the attached file. From there, it is clear that the functions are reflections over Y-axis, not reflections over X-axis.
So, options (A) is incorrect and option (B) is correct.
From the table, we have
[tex]f(-2)=\dfrac{1}{4},~~f(-1)=\dfrac{1}{2},~~f(0)=1,~~f(1)=2,~~f(2)=4,\\\\g(-2)=4,~~g(-1)=2,~~g(0)=1,~~g(1)=\dfrac{1}{2},~~g(2)=\dfrac{1}{4}.[/tex]
So, as the value of 'x' increases, the value of f(x) increases and value of y(x) decreases.
Therefore, f(x) is an increasing function and g(x) is a decreasing function. So, option (C) is incorrect.
Also, we have
[tex]f(0)=g(0)=1.[/tex]
So, both the functions have same initial value. So, option (D) is also incorrect.
Thus, the correct conclusion is (B) The functions f(x) and g(x) are reflections over the y-axis.