The equation is .
The base of the plate is beneath the surface of the water.
Observe the graph:
\The height of the vertical plate is .
The horizontal length of the vertical plate is .
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Therefore, .
The fluid force is .
The limits are to
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The weight density of water is .
Substitute ,
and
.
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Consider the integrand as function .
Graph:
\Graph the function :
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Observe the graph:
\.
.
Therefore, .
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