La cantidad de automóviles que pasaron por hora por una estación de peaje en una muestra de 8 hs es

Exercise 3.5. For each of the following functions determine the inverse image of T = {x ∈ R : 0 ≤ [x^2 − 25}.

masya89 [10]

a. The inverse image of f(x) is f⁻¹(x) = ∛(x/3)

b. The inverse image of g(x) is $g^{-1}(x) = e^{x}$

c. The inverse image of <u>h</u>(x) is h⁻¹(x) = x + 9

<h3 /><h3>The domain of T</h3>

Since T = {x ∈ R : 0 ≤ [x^2 − 25} ⇒ x² - 25 ≥ 0

⇒ x² ≥ 25

⇒ x ≥ ±5

⇒ -5 ≤ x ≤ 5.

<h3>Inverse image of f(x)</h3>

The inverse image of f(x) is f⁻¹(x) = ∛(x/3)

f : R → R defined by f(x) = 3x³

Let f(x) = y.

So, y = 3x³

Dividing through by 3, we have

y/3 = x³

Taking cube root of both sides, we have

x = ∛(y/3)

Replacing y with x we have

y = ∛(x/3)

Replacing y with f⁻¹(x), we have

So, the inverse image of f(x) is f⁻¹(x) = ∛(x/3)

<h3>Inverse image of g(x)</h3>

The inverse image of g(x) is $g^{-1}(x) = e^{x}$

g : R+ → R defined by g(x) = ln(x).

Let g(x) = y

y = ln(x)

Taking exponents of both sides, we have

$e^{y} = e^{lnx} \\e^{y} = x$

Replacing x with y, we have

$y = e^{x}$

Replacing y with g⁻¹(x), we have

So, the inverse image of g(x) is $g^{-1}(x) = e^{x}$

<h3>Inverse image of h(x)</h3>

The inverse image of <u>h</u>(x) is h⁻¹(x) = x + 9

h : R → R defined by h(x) = x − 9

Let y = h(x)

y = x - 9

Adding 9 to both sides, we have

y + 9 = x

Replacing x with y, we have

x + 9 = y

Replacing y with h⁻¹(x), we have

So, the inverse image of <u>h</u>(x) is h⁻¹(x) = x + 9

Learn more about inverse image of a function here:

brainly.com/question/9028678

5 0

2 years ago

Skyscraper Windows

Musya8 [376]

Answer:

A.) $2,166

B.) $10,545

C.) (n/2)(3.5 + 0.5n) × 38

Step-by-step explanation:

Floor - - - - - - - - - - 1 - - - - - - - 2 - - - - - - - 3

Cost / window - - $2.00 - - - $2.50 - - - $3.00

Cost of washing first floor = $2 × 38

Cost of second floor is: (2 + 0.5) × 38

Cost of third floor is: (2 + 2 × 0.5) × 38

Cost of n floor : (2 + (n - 1) × 0.5) × 38

Therefore,

Total cost :

(2 + (2 + 0.5) + (2 + 2*0.5) + ... + (2 + (n - 1)*0.5)) × 38

Using Arithmetic progression for the sequence :

2, (2 + 0.5), (2 + 2*0.5),..., (2 + (n - 1)*0.5)

first term 'a' = 2; common difference 'd' = 0.5

Sum of the first n terms of arithmetic sequence terms is:

S = (n/2)(2a + (n - 1)d) ; Where a = 2 and d = 0.5

S = (n/2)(2*2 + (n - 1)*0.5)

S = (n/2)(4 + 0.5n - 0.5)

S = (n/2)(3.5 + 0.5n)

To wash all windows with n stories :

S × 38 windows

A.) To wash all windows : stories = 12

n = 12

(12/2)(3.5 + 0.5(12)) × 38

6(3.5 + 6) × 38 = $2,166

B.) if building is 30 stories tall:

n = 30

(30/2)(3.5 + 0.5(30)) × 38

15(3.5 + 15) × 38 = $10,545

C.) If building is n stories tall :

(n/2)(3.5 + 0.5n) × 38

4 0

3 years ago

Factor completely 2x2 − 2x − 40

Montano1993 [528]

Answer:

2(x-5)(x+4)

Step-by-step explanation:

2x^2 − 2x − 40

Factor out a 2

2(x^2 -x -20)

What 2 numbers multiply to -20 and add to -1

-5*4 = -20

-5+4 = -1

2(x-5)(x+4)

4 0

3 years ago

A student scored in the 60th percentile on her math exam. What does this student's score mean in relation to those of the other

Andrei [34K]

Answer:

The correct option is;

c. Her score was better than those of 60% of all test takers

Step-by-step explanation:

Percentile Score is the score of an exam or test candidate with regard to the relative performance of the other persons that took part in the exam or test.

The percentile score is calculated by converting candidates scores into a scale consisting of the scores of all candidates and ranging from 0 to 100

A 60th percentile score means that the student performed better than 60% of all the candidates of the test and 40% of the test takers scored the same as or better than the student.

5 0

3 years ago

55x - 21a ..............

RoseWind [281]

What is the question?

8 0

3 years ago