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avatar+2 
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we'll start by finding the function f(x) that satisfies the given conditions.

To find f(x), let's solve the differential equation f'(x) = f(x) + e^x + x^2 - 2. We can rewrite the equation as:

f'(x) - f(x) = e^x + x^2 - 2.

This is a linear first-order differential equation, and we can solve it using an integrating factor. The integrating factor is given by the exponential of the integral of the coefficient of f(x), which is -1 in this case:

μ(x) = e^(-x).

Multiplying both sides of the differential equation by μ(x), we have:

e^(-x) * [f'(x) - f(x)] = e^(-x) * (e^x + x^2 - 2).

Simplifying the equation, we get:

(e^(-x) * f'(x)) - (e^(-x) * f(x)) = 1 + x^2e^(-x) - 2e^(-x).

Now, notice that the left-hand side is the derivative of (e^(-x) * f(x)) with respect to x. Applying the chain rule, we have:

d/dx (e^(-x) * f(x)) = 1 + x^2e^(-x) - 2e^(-x).

Integrating both sides with respect to x, we obtain:

∫ d/dx (e^(-x) * f(x)) dx = ∫ (1 + x^2e^(-x) - 2e^(-x)) dx.

The integral on the left-hand side can be written as:

e^(-x) * f(x) = ∫ (1 + x^2e^(-x) - 2e^(-x)) dx.

Simplifying the right-hand side, we have:

e^(-x) * f(x) = x - x^2 - 2x + c,

where c is a constant of integration.

To determine the constant c, we use the initial condition f(0) = 1. Plugging in x = 0 and f(x) = 1 into the equation above, we get:

e^(0) * 1 = 0 - 0^2 - 2(0) + c, 1 = c.

Therefore, the equation becomes:

e^(-x) * f(x) = x - x^2 - 2x + 1.

Now, let's solve each part of the problem based on the function we obtained.

a) To find f(1), we substitute x = 1 into the equation:

e^(-1) * f(1) = 1 - 1^2 - 2(1) + 1, e^(-1) * f(1) = -1.

Dividing both sides by e^(-1), we get:

f(1) = -e.

So, the value of f(1) is approximately -2.71828.

b) To find the x-coordinate(s) where the graph of f(x) has a horizontal tangent, we need to find the points where f'(x) = 0.

Given that f'(x) = f(x) + e^x + x^2 - 2, we set f'(x) = 0:

f(x) + e^x + x^2 - 2 = 0.

Unfortunately, finding an analytical solution for this equation is not straightforward. We can use numerical methods such as Newton's method or graphing techniques,also if you have some problems with books and want to write some essays you can access http://supremestudy.com/essay-examples/animal-testing and see diverse essays on different topics from maths to animal testings ! to approximate the x-coordinate(s) where the graph of f(x) has horizontal tangents.

c) To determine the value of the definite integral from 0 to 1 of f(x) with respect to x, we evaluate the integral:

∫[0 to 1] f(x) dx.

We can rewrite the integral using the equation we obtained earlier:

∫[0 to 1] (e^(-x) * f(x)) dx = ∫[0 to 1] (x - x^2 - 2x + 1) dx.

Integrating term by term, we have:

∫[0 to 1] (x - x^2 - 2x + 1) dx = [1/2 * x^2 - 1/3 * x^3 - x^2/2 + x] evaluated from 0 to 1.

Evaluating the integral limits, we get:

[1/2 * (1)^2 - 1/3 * (1)^3 - (1)^2/2 + 1] - [1/2 * (0)^2 - 1/3 * (0)^3 - (0)^2/2 + 0],

[1/2 - 1/3 - 1/2 + 1] - [0],

1/6.

So, the value of the definite integral from 0 to 1 of f(x) with respect to x is 1/6.
hah that took quite a while!

Jun 29, 2023
 #2
avatar+2435 
0

 

what is the size of an exterior angle of a regular polygon with 180 sides.   

 

The sum of the interior angles   

of a regular polygon is   

                                                   total  =  (n – 2)(180o)   

                                                   where n is the number of sides  

 

The total for 180 sides is           

                                                   total  =  (180 – 2)(180o)  

                                                   total  =  178 • 180o  =  32,040o   

 

That's the total.  Each angle

would be the total divided by  

the number of sides.     

                                                                                            32,040o  

                                                   a single interior angle  =  ––––––––    

                                                                                               180   

 

                                                   a single interior angle  =  178o     

 

I see now that I should have anticipated that answer and done it in my head. 

 

An exterior angle is 180o minus the interior angle. Visualize extending a side   

beyond the angle.  A straight line contains 180o   

 

                                                    exterior angle  =  180o – 178o  =  2o   

.

Jun 29, 2023
 #1
avatar+2435 
0

 

I have to paint one side of a wall.  The wall is 12 meters tall and 120 meters long.  Each gallon of paint covers 150 square feet. If a foot is approximately 0.3048 meters, then what is the smallest whole number of gallons I can buy and have enough paint to cover the whole wall?  

 

 

You're going to have to convert those meters to square feet,  

so I think it's better to do it from the start.  Even though we'll  

have fractions to contend with, a calculator makes that easy.  

 

                                                                       12 m  

1 foot is 0.3048 meter, so the height is       –––––––––  =  39.3701 ft   

                                                                   0.3048 m/ft  

 

                                                                       120 m  

1 foot is 0.3048 meter, so the length is       –––––––––  =  393.7007 ft   

                                                                   0.3048 m/ft  

 

Area is height times length     (39.3701 ft)(393.7007 ft)  =  15,500.0359 sq ft  

 

1 gallon will cover 150 sq ft  

so divide that into the area               15,500.0359 sq ft  

                                                        –––––––––––––––  =  103.3335 gallons  

                                                           150 sq ft/gallon  

 

You can't buy just part of a gallon of paint,  

so we have to round that up to whole gallons                       104 gallons  

.

Jun 29, 2023
 #3
avatar+131 
+1

 

If I give my brother 5 dollars, then we will have the same amount of money. If instead he gives me 25 dollars, then I'll have twice as much money as he will have. How much money does my brother currently have (in dollars)?   

 

Let M stand for My original amount  

Let B stand for Brother's original amount   

 

                                                             (M – 5)  =  (B + 5)   

                                                             (M + 25)  =  (2)(B – 25)  

 

                                                              M – 5  =  B + 5   gives us  M = B + 10    (1)  

 

                                                              M + 25  =  2B – 50                                 (2)  

 

Substitute the value of M from (1)   

into the equation (2)                             B + 10 + 25  =  2B – 50   

 

Combine like terms                                          85  =  B    

 

Brother has 85 dollars before they start giving each other money.   

 

The problem doesn't ask for My original amount but it's B + 10 = 95  

 

Check answer  

 

If I give my brother 5, then I'll have 90 and so will he, so we have the same.  

If my brother gives me 25, then I'll have 120 and my brother will have 60. 

Jun 29, 2023
 #3
avatar+2435 
0

 

If I give my brother 5 dollars, then we will have the same amount of money. If instead he gives me 25 dollars, then I'll have twice as much money as he will have. How much money does my brother currently have (in dollars)?   

 

Let M stand for My original amount  

Let B stand for Brother's original amount   

 

                                                             (M – 5)  =  (B + 5)   

                                                             (M + 25)  =  (2)(B – 25)  

 

                                                              M – 5  =  B + 5   gives us  M = B + 10    (1)  

 

                                                              M + 25  =  2B – 50                                 (2)  

 

Substitute the value of M from (1)   

into the equation (2)                             B + 10 + 25  =  2B – 50   

 

Combine like terms                                          85  =  B    

 

Brother has 85 dollars before they start giving each other money.   

 

The problem doesn't ask for My original amount but it's B + 10 = 95  

 

Check answer  

 

If I give my brother 5, then I'll have 90 and so will he, so we have the same.  

If my brother gives me 25, then I'll have 120 and my brother will have 60.  

.

Jun 29, 2023
 #1
avatar+131 
+1

Real numbers a and b satisfy  

a + ab = 250  

a - ab = -240  

Enter all possible values of a, separated by commas.  

 

 

If you add the two equations together                a + ab  =   250  

                                                                           a – ab  = –240  

                                                                          ———————  

you get                                                              2a         =  10  

 

from which                                                                  a  =  5  

 

The problem doesn't ask for b,  

but ... find b by substituting  

a back into a + ab = 250                                    5 + 5b  =  250  

                                                                                5b  =  245  

                                                                                  b  =  49  

 

check b by substituting  

a back into a – ab = –240                                  5 – 5b  =  –240  

                                                                              –5b  =  –245  

                                                                                  b  =  49  

Jun 29, 2023
 #1
avatar+131 
0
Jun 29, 2023

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