Solve Wave Superposition: 2Asin(7π(x+vt)) cos (3π(x+vt)) at t=0

AI Thread Summary
The discussion revolves around solving the wave superposition equation 2Asin(7π(x + vt)) cos(3π(x + vt)) at t=0 for maximum and minimum displacement locations. The waves have wavelengths of 0.5m and 0.2m, with equal amplitude and velocity. The user successfully derived the equation but encountered difficulties in finding critical points due to calculator limitations. After resolving the calculator issue, they were able to proceed with the solution. The conversation highlights the challenges of graphing small values in wave equations.
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Homework Statement


Two waves are produced on a string with length of 1m. Wavelength of one is .5m Wavelength of the other is .2m. Amplitude and velocity are the same.
Show that 2Asin(7pi(x + vt)) cos(3pi(x + vt)).
At t=0 what locations are the max/min displacement at?

Homework Equations





The Attempt at a Solution


I can solve the first part no problem. We have Eq we needed to show. Then I take z'(x) and have 2pi*A(2cos(4pi*x)+5cos(10pi*x)) and = 0 to get crit points.. This is where I am stuck. My calculator is unable to compute the graph at such small y apparently. I was unfortunately unable to find anything on the internet on how to solve this. Any help would be greatly appreciated.
 
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So you I fixed my calculator, problem solved ><
 
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