Thank you for help
But I think it is not good answer for me.
I want to express that if μ is 0.5, a2 is 0.3274.
it means that a2 values must write for indication of x-axis.
Also Could I give your another question?
I don't know why a2(a1,μ) on left and a2(a1,μ) on right in picture are different
How I can make these values to be same?