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

Replace x with π/2 - x to get the equivalent integral

but the integrand is even, so this is really just

Substitute x = 1/2 arccot(u/2), which transforms the integral to

There are lots of ways to compute this. What I did was to consider the complex contour integral

where γ is a semicircle in the complex plane with its diameter joining (-R, 0) and (R, 0) on the real axis. A bound for the integral over the arc of the circle is estimated to be

which vanishes as R goes to ∞. Then by the residue theorem, we have in the limit

and it follows that

The complete question in the attached figure
Part a)
we know that
ABC is a right triangle
∠ACB=45°
AC=hypotenuse------> 6√2 cm
sin 45=AB/AC-----> AB=AC*sin 45----> AB=6√2*√2/2----> AB=6 cm
the answer part a) isAB=6 cmPart b)
we know that
volume of the pyramid=(1/3)*Area of the base*height
area of the base=50 cm²
height=6 cm
so
volume of the pyramid=(1/3)*50*6----> 100 cm³
the answer part b) is 100 cm³
Using an linear function, we find that by 2020 only 11% of all American adults believe that most qualified students get to attend college.
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A decaying linear function has the following format:

In which
- A(0) is the initial amount.
- m is the slope, that is, the yearly decay.
- In 2000, 45% believed, thus,

- Decaying by 1.7 each year, thus
.
The equation is:

It will be 11% in t years after 2000, considering t for which A(t) = 11, that is:




2000 + 20 = 2020
By 2020 only 11% of all American adults believe that most qualified students get to attend college.
A similar problem is given at brainly.com/question/24282972
Answer:
48,000
Step-by-step explanation:
320,000÷100=3200
1/100=3200
×15=48,000
therefore 15/100=48,000