Answer:
See Explanation.
General Formulas and Concepts:
<u>Pre-Algebra</u>
- Distributive Property
- Equality Properties
<u>Algebra I</u>
- Combining Like Terms
- Factoring
<u>Calculus</u>
- Derivative 1:
![\frac{d}{dx} [e^u]=u'e^u](https://tex.z-dn.net/?f=%5Cfrac%7Bd%7D%7Bdx%7D%20%5Be%5Eu%5D%3Du%27e%5Eu)
- Integration Constant C
- Integral 1:

- Integral 2:

- Integral 3:

- Integral Rule 1:

- Integration by Parts:

- [IBP] LIPET: Logs, Inverses, Polynomials, Exponents, Trig
Step-by-step Explanation:
<u>Step 1: Define Integral</u>

<u>Step 2: Identify Variables Pt. 1</u>
<em>Using LIPET, we determine the variables for IBP.</em>
<em>Use Int Rules 2 + 3.</em>

<u>Step 3: Integrate Pt. 1</u>
- Integrate [IBP]:

- Integrate [Int Rule 1]:

<u>Step 4: Identify Variables Pt. 2</u>
<em>Using LIPET, we determine the variables for the 2nd IBP.</em>
<em>Use Int Rules 2 + 3.</em>

<u>Step 5: Integrate Pt. 2</u>
- Integrate [IBP]:

- Integrate [Int Rule 1]:

<u>Step 6: Integrate Pt. 3</u>
- Integrate [Alg - Back substitute]:
![\int {e^{au}sin(bu)} \, du = \frac{-e^{au}cos(bu)}{b} + \frac{a}{b} [\frac{e^{au}sin(bu)}{b} - \frac{a}{b} \int ({e^{au} sin(bu)}) \, du]](https://tex.z-dn.net/?f=%5Cint%20%7Be%5E%7Bau%7Dsin%28bu%29%7D%20%5C%2C%20du%20%3D%20%5Cfrac%7B-e%5E%7Bau%7Dcos%28bu%29%7D%7Bb%7D%20%2B%20%5Cfrac%7Ba%7D%7Bb%7D%20%5B%5Cfrac%7Be%5E%7Bau%7Dsin%28bu%29%7D%7Bb%7D%20-%20%5Cfrac%7Ba%7D%7Bb%7D%20%5Cint%20%28%7Be%5E%7Bau%7D%20sin%28bu%29%7D%29%20%5C%2C%20du%5D)
- [Integral - Alg] Distribute Brackets:

- [Integral - Alg] Isolate Original Terms:

- [Integral - Alg] Rewrite:

- [Integral - Alg] Isolate Original:

- [Integral - Alg] Rewrite Fraction:

- [Integral - Alg] Combine Like Terms:

- [Integral - Alg] Divide:

- [Integral - Alg] Multiply:
![\int {e^{au}sin(bu)} \, du = \frac{1}{a^2+b^2} [ae^{au}sin(bu) - be^{au}cos(bu)]](https://tex.z-dn.net/?f=%5Cint%20%7Be%5E%7Bau%7Dsin%28bu%29%7D%20%5C%2C%20du%20%3D%20%5Cfrac%7B1%7D%7Ba%5E2%2Bb%5E2%7D%20%5Bae%5E%7Bau%7Dsin%28bu%29%20-%20be%5E%7Bau%7Dcos%28bu%29%5D)
- [Integral - Alg] Factor:
![\int {e^{au}sin(bu)} \, du = \frac{e^{au}}{a^2+b^2} [asin(bu) - bcos(bu)]](https://tex.z-dn.net/?f=%5Cint%20%7Be%5E%7Bau%7Dsin%28bu%29%7D%20%5C%2C%20du%20%3D%20%5Cfrac%7Be%5E%7Bau%7D%7D%7Ba%5E2%2Bb%5E2%7D%20%5Basin%28bu%29%20-%20bcos%28bu%29%5D)
- [Integral] Integration Constant:
![\int {e^{au}sin(bu)} \, du = \frac{e^{au}}{a^2+b^2} [asin(bu) - bcos(bu)] + C](https://tex.z-dn.net/?f=%5Cint%20%7Be%5E%7Bau%7Dsin%28bu%29%7D%20%5C%2C%20du%20%3D%20%5Cfrac%7Be%5E%7Bau%7D%7D%7Ba%5E2%2Bb%5E2%7D%20%5Basin%28bu%29%20-%20bcos%28bu%29%5D%20%2B%20C)
And we have proved the integration formula!
The area of a square is the length of a side times itself:
2_4/9 * 2_4/9
Mixed numbers cannot be multiplied, so first convert to improper fractions:
(9*2)+4 = 18+4 = 22/9
22/9 * 22/9
Multiply straight across:
(22*22)/(9*9) = 484/81
Now turn this into a mixed number:
81 goes into 484 five times with 79 left over:
5_79/81 square inches
Since this is not one of the answer choices, I'm wondering if the given length of the side of the square is incorrect?
C I need to put 20 letters so yea the answer is C
<h3>
<u>Answer</u><u>:</u></h3>

<h3>
<u>Explan</u><u>ation</u><u>:</u></h3>
First, convert any mixed numbers to fractions. An easy way to convert:

<h3>
=</h3>

Then, apply the fractions formula for division.

Then, simplify.

Answer:
b = 81
Step-by-step explanation:
given a² and b are directly proportional then the equation relating them is
a² = kb ← k is the constant of proportionality
to find k use the condition a = 2 when b = 9 , then
2² = 9k
4 = 9k ( divide both sides by 9 )
= k
a² =
b ← equation of proportion
when a = 6 , then
6² =
b
36 =
b ( multiply both sides by 9 to clear the fraction )
324 = 4b ( divide both sides by 4 )
81 = b