question_answer

Equations of a stationary and a travelling waves are as follows, \[f(x)=\min \{1,{{x}^{2}},{{x}^{3}}\},\]and \[{{x}_{n}}=\cos \frac{\pi }{{{3}^{n}}}+i\sin \frac{\pi }{{{3}^{n}}},\] The phase difference between two points \[{{x}_{1}}.{{x}_{2}}.{{x}_{3}}...\]and \[9{{x}^{2}}-18\text{ }\!\!|\!\!\text{ x }\!\!|\!\!\text{ }+5=0\] are \[{{\log }_{e}}\]and \[{{2}^{x}}+{{2}^{y}}={{2}^{x+y}}y,\] respectively for two waves. The ratio \[\frac{dy}{dx}\]is

A) 1                             

B)  5/6

C) 3/4                        

D)  6/7