a) The first integral corresponds to the area under y = f(x) on the interval [0, 3], which is a right triangle with base 3 and height 5, hence the integral is

$\displaystyle \int_0^3 f(x) \, dx = \frac12 \times 3 \times 5 = \boxed{\frac{15}2}$

b) The integral is zero since the areas under the curve over [3, 4] and [4, 5] are equal but opposite in sign. In other words, on the interval [3, 5], f(x) is symmetric and odd about x = 4, so

$\displaystyle \int_3^5 f(x) \, dx = \int_3^4 f(x) \, dx + \int_4^5 f(x) \, dx = \int_3^4 f(x) \, dx - \int_3^4 f(x) \, dx = \boxed{0}$

c) The integral over [5, 9] is the negative of the area of a rectangle with length 9 - 5 = 4 and height 5, so

$\displaystyle \int_5^9 f(x) \, dx = -4\times5 = -20$

Then by linearity, we have

$\displaystyle \int_0^9 f(x) \, dx = \left\{\int_0^3 + \int_3^5 + \int_5^9\right\} f(x) \, dx = \frac{15}2 + 0 - 20 = \boxed{-\frac{25}2}$

8 0

2 years ago

If you on a motorcycle trip of 30 miles in the and 5\19 of the trip is downhill, how many miles of the trip are not downhill? Re

Bess [88]

Answer:

1/4 of the trip is not down hill

8 0

3 years ago

A store had 112 diet sodas. The ratio of diet sodas to regular sodas was 8:4. How many regular sodas were there?

IceJOKER [234]

Answer:

Step-by-step explanation:

There are two ways the answer to this question can be determined

Method 1 : the fast method

We know that 8 is twice 4

4 x 2 = 8

The ratio of diet soda = 8

the ratio of regular sodas = 4

Diet sodas = 112

the number of regular sodas = 112 / 2 = 56

Method 2 : The long method

I would first determine the total number of diet and regular sodas. Let the total number be represented by d

from the question, the following equation can be derived :

(8/12) x d = 112

divide both sides of the equation by 12/8 to determine the value of d

d = 112 x (12/8) = 168

We can now derive a value for the number of regular soda

regular sodas = ( ratio of regular sodas / total soda) x total number of sodas

(4/12) x 168 = 56

3 0

3 years ago

Solve the equation 4(x – 2) = 3x + 1. Question 15 options: A) 3 B) 8 C) 9 D) 2

telo118 [61]

Answer:

x = 9

Step-by-step explanation:

Step 1: Write equation

4(x - 2) = 3x + 1

Step 2: Solve for x

Distribute 4: 4x - 8 = 3x + 1
Subtract 3x on both sides: x - 8 = 1
Add 8 to both sides: x = 9

Step 3: Check

Plug in x to verify it's a solution.

Substitute: 4(9 - 2) = 3(9) + 1
Parenthesis (add): 4(7) = 3(9) + 1
Multiply: 28 = 27 + 1
Add: 28 = 28

5 0

4 years ago