Cecil Moore wrote:

Set the two waves to equal magnitudes and opposite phases.
Hint: there can be no wave cancellation without waves.

More to the point, there can be no waves under the conditions you
describe. So, again, just when do these waves actually exist, Cecil?
We apparently agree that it's not when they cancel. The only other
possibility I can think of would be when they don't cancel. So, when
don't they cancel? Does it occur in steady state?

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