All categories

3 years ago

How would I do question 5 I don’t understand

Mathematics

1 answer:

bazaltina [42]3 years ago

4 0

Answer:

a) f(0)=4

b) f(-2)=2

c) x∈{-8,-4,4,8}

d) x∈{-9,-3,3,9}

e) x∈(-∞,-9)∪(-3,3)∪(9,∞).

f) x∈[-9,-3]∪[3,9]

g) Domain is x∈[-10,10]. Range is y∈[-4,4]. Zeros are at elements of x in {-9,-3,3,9}

h) Increasing on x∈ (-6,0) ∪ (6,10) and

decreasing on x∈ (-10,-6) ∪ (0,6).

Step-by-step explanation:

a) f(0) means what is the y-coordinate of the point at x=0.

So find 0 on the x-axis. I'm going to go up because the curve is at y=4 there.

Conclusion: f(0)=4.

b) f(-2) means what is the y-coordinate of the point at x=-2.

So find -2 on the x-axis. I'm going to go up because the curve is at y=2 there.

Conclusion: f(-2)=2.

c) f(x)=-2 means what is x when y=-2. So go on the y-axis and find -2. Now anything on that line y=-2 (horizontal line going through y=-2 on the y-axis) we need to look at.

There are 4 value we need to look at then.

x=-8

x=-4

x=4

x=8

At all of these the y-coordinate is -2.

d) f(x)=0 means what is x when y=0. So go on the y-axis and find 0. Now anything on that line y=0 (horizontal line going through y=0 on the y-axis; also knowing as the x-axis for y=0) we need to look at.

There are 4 values we need to look at then.

x=-9

x=-3

x=3

x=9

e) f(x)>0 means where is the curve above the x-axis.

The curve is above the x-axis:

Before x=-9
Between x=-3 and x=3
After x=9

The interval notation is:

(-∞,-9)∪(-3,3)∪(9,∞).

d) f(x)≥0 means where is the curve below or on the x-axis (also known as y=0).

The curve is below or on the x-axis:

Between -9 and -3 (inclusive of both endpoints because they include y=0).
Between 3 and 9 (inclusive of both endpoints because they include y=0).

The interval notation is:

[-9,-3]∪[3,9]

g) The domain is where the curve exists for the x-values.

The domain is all real numbers between -10 and 10 (inclusive of both).

The curve starts at x=-10 and stops at x=10. The function exists a y value for any number between -10 and 10 (including both).

Interval notation is:

[-10,10]

The range is where the curve exists for the y-values.

Looking from bottom to top I see that it starts at y=-4 and stops at y=4. I notice the curve exists at some point between those two horizontal lines. It also exists at both of those endpoints" -4 and 4.

The range is between -4 and 4 (including both).

Interval notation is:

[-4,4]

The zeros are where the graph crosses the x-axis.

The graph crosses the x-axis at:

x=-9

x=-3

x=3

x=9

h) Reading left to right the graph increases when you see the curve going up.

I see this from x=-6 to x=0 (exclusive of both).

I see this from x=6 to x=10 (exclusive of both).

So interval notation is (-6,0) ∪ (6,10).

Reading left to right the graph decreases when you see the curve going down.

I see this from x=-10 to x=-6 ( exclusive of both).

I see this from x=0 to x=6 (exclusive of both).

You might be interested in

The probability that your call to a service line is answered in less than 30 seconds is 0.85. Assume that your calls are indepen

aev [14]

Answer:

a) 0.1720

b) 0.8298

c) 19

Step-by-step explanation:

For each call, there are only two possible outcomes. Either they are answered in less than 30 seconds. Or they are not. The probabilities for each call are independent. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

In this problem we have that:

$p = 0.85$

(a) If you call 12 times, what is the probability that exactly 9 of your calls are answered within 30 seconds? Round your answer to four decimal places (e.g. 98.7654).

This is $P(X = 9)$ when $n = 12$ .

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 9) = C_{12,9}.(0.85)^{9}.(0.15)^{3} = 0.1720$

(b) If you call 20 times, what is the probability that at least 16 calls are answered in less than 30 seconds? Round your answer to four decimal places (e.g. 98.7654).

This is $P(X \geq 16)$ when $n = 20$

$P(X \geq 16) = P(X = 16) + P(X = 17) + P(X = 18) + P(X = 19) + P(X = 20)$

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 16) = C_{20,16}.(0.85)^{16}.(0.15)^{4} = 0.1821$

$P(X = 17) = C_{20,17}.(0.85)^{17}.(0.15)^{3} = 0.2428$

$P(X = 18) = C_{20,18}.(0.85)^{18}.(0.15)^{2} = 0.2293$

$P(X = 19) = C_{20,19}.(0.85)^{19}.(0.15)^{1} = 0.1368$

$P(X = 20) = C_{20,20}.(0.85)^{20}.(0.15)^{0} = 0.0388$

$P(X \geq 16) = P(X = 16) + P(X = 17) + P(X = 18) + P(X = 19) + P(X = 20) = 0.1821 + 0.2428 + 0.2293 + 0.1368 + 0.0388 = 0.8298$

(c) If you call 22 times, what is the mean number of calls that are answered in less than 30 seconds? Round your answer to the nearest integer.

The expected value of the binomial distribution is:

$E(X) = np$

In this question, we have $n = 22$

$E(X) = 22*0.85 = 18.7$

The nearest integer to 18.7 is 19.

7 0

3 years ago

Is sin A is 7/10 what is Cos A

viva [34]

Answer:

Cos A = (√51)/ 10

Step-by-step explanation:

sin is opposite/hypothenuse

cos is adjacent/hypothenuse

Pythagorus theorem says that c² = a² + b²

10² = 7² + b²

b² = 100 - 49

b = ±√51

It doesn't make sense for a length to be a minus number therefore, we will use +√51.

Cos A = (√51)/ 10

Tell me if I am wrong.

Can I get brainliest

5 0

3 years ago

Lalo has 1500 minutes per month on his cell phone plan. How many more minutes can he use if he has already talked for 785 minute

SVEN [57.7K]

1500 - 785 = 715
number of minutes per month - number of minutes used = number of minutes left.

8 0

3 years ago

We can calculate the depth ddd of snow, in centimeters, that accumulates in Harper's yard during the first hhh hours of a snowst

inna [77]

Answer:

0.2 hours

Step-by-step explanation:

The depth, d of snow (in cm) that accumulates in Harper's yard during the first h hours of a snowstorm can be calculated using the equation:

d=5h

When d=1cm, we want to determine the value of h.

1=5h

h=1/5=0.2

Therefore, it takes 0.2 hours for 1 centimeter of snow to accumulate in Harper's yard.

3 0

3 years ago

8. what is the volume of these 5 objects

wel

Answer:

1) B

Step-by-step explanation:

To get the volume of a cube, you multiply the length, width and height together. 4 x 7 x 8 = 224. 8 × 5 × 6 = 240. This means that chocolate box B has the larger volume.

6 0

3 years ago