Answer:
So, solution of the differential equation is
Step-by-step explanation:
We have the given differential equation: y′′+4y=5xcos(2x)
We use the Method of Undetermined Coefficients.
We first solve the homogeneous differential equation y′′+4y=0.
It is a homogeneous solution:
Now, we finding a particular solution.
we get
So, solution of the differential equation is
Answer:
48 feet
Step-by-step explanation:
At a particular time, objects and their shadows are proportionate.
Therefore, in figure,
AB/FD = BC/DE --- (1)
where AB is the height of the lighthouse, BC, its shadow and FD is the height of Zara and DE is her shadow.
From the given information,
BC = 36 feet
FD = 4 feet and DE = 3 feet
(1) becomes
AB/4 = 36/3
AB = 12
AB = 48
Hence, the height of the lighthouse is 48 feet.
Answer:
a. around 36.36 hours; around 28.57 hours
b. $134.21; $159.38
Step-by-step explanation: