Answer:
7.5
Step-by-step explanation:
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Simplify what's in brackets first, then move to what's in the parenthesis
Answer:
b
Step-by-step explanation:
second option 400/3
Answer:
the required equation is; y = 21 sin(πt/6)
Step-by-step explanation:
Given the data in the question;
Water rises above sea level = 21 ft
Water drops below sea level = 21 ft
so
maximum = 21 ft and also
minimum = 21 ft
Amplitude = ( maximum + minimum ) / 2
Amplitude = ( 21 + 21 ) / 2
Amplitude = ( 21 + 21 ) / 2 = 42/2 = 21 ft
Period = 12 hours
and we know that; period = 2π/b
so
12 = 2π/b
12b = 2π
b = 2π / 12
b = π/6
Standard equation for simple harmonic is; y = asin(bt)
we substitute
y = 21 sin(πt/6)
Hence the required equation is; y = 21 sin(πt/6)