In this exercise we have to calculate the value of the water depth, so we have: d=5.5Cos(12t)+6
A periodic wave is a wave with a repeating continuous pattern that determines its wavelength and frequency
Putting together some information given in the statement we have:
Knowing that the formula will be given by an equation similar to:
[tex]d=acos(bt)+k[/tex]
Where:
The amplitude difference is given by:
[tex]8.75-3.25=5.5\ m[/tex]
The mean depth is:
[tex]k=\dfrac{(3.25+8.75)}{2}=6\ m[/tex]
Then writing the equation with;
[tex]d=acos(bt)+k\\\\d=5.5cos(12t)+6[/tex]
Hence the value of water depth will be d=5.5Cos(12t)+6
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