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Question
A wave is represented by an equation \[y = c_1 \sin \left( c_2 x + c_3 t \right)\] In which direction is the wave going? Assume that \[c_1 , c_2\] \[c_3\] are all positive.
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Solution
Equation of the wave is \[y = c_1 \sin \left( c_2 x + c_3 t \right)\]
When the variable of the equation is (c2x + c3t), then the wave must be moving in the negative x-axis with time t.
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