Let a=⟨1,−4,2⟩ and b=⟨−5,−5,−2⟩. Compute:
a+b=⟨ ,, ⟩
a−b=⟨ ,,⟩
2a=⟨ ,,⟩
3a+4b=⟨ ,, ⟩
|a|=
Answer:
a + b = ⟨-4, -9, 0⟩
a - b = ⟨6, 1, 4⟩
2a = ⟨2, -8, 4⟩
3a + 4b = ⟨-17, -32, -2⟩
|a| = √21
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightPre-Calculus
Vectors
OperationsScalars[Magnitude] ||v|| = √(x² + y² + z²)Step-by-step explanation:
Adding and subtracting vectors are follow the similar pattern of normal order of operations:
a + b = ⟨1 - 5, -4 - 5, 2 - 2⟩ = ⟨-4, -9, 0⟩
a - b = ⟨1 + 5, -4 + 5, 2 + 2⟩ = ⟨6, 1, 4⟩
Scalar multiplication multiplies each component:
2a = ⟨2(1), 2(-4), 2(2)⟩ = ⟨2, -8, 4⟩
Remember to multiply in the scalar before doing basic operations:
3a + 4b = ⟨3(1), 3(-4), 3(2)⟩ + ⟨4(-5), 4(-5), 4(-2)⟩ = ⟨3, -12, 6⟩ + ⟨-20, -20, -8⟩ = ⟨-17, -32, -2⟩
Absolute values surrounding a vector signifies magnitude of a vector. Follow the formula:
|a| = √[1² + (-4)² + 2²] = √21
Answer pleaseeeeeeee
Answer:
17x^2-9x-9 -->B
Step-by-step explanation:
7x^2 -12x +3 +10x^2+3x-12
Given $f(x) = \frac{\sqrt{2x-6}}{x-3}$, what is the smallest possible integer value for $x$ such that $f(x)$ has a real number value? Please show steps. Thank you!
(I rewrote the question without the symbols, they are the same question)
Given f(x) = {2x-6}/{x-3}, what is the smallest possible integer value for x such that f(x) has a real number value? Thank you!
===========================================================
Explanation:
The given function is
[tex]f(x) = \frac{\sqrt{2x-6}}{x-3}[/tex]
which is the same as writing f(x) = ( sqrt(2x-6) )/(x-3)
The key for now is the square root term. Specifically, the stuff underneath. This stuff is called the radicand.
Recall that the radicand cannot be negative, or else the square root stuff will result in a complex number. Eg: [tex]\sqrt{-4} = 0+2i[/tex]
The question is basically asking: what is the smallest x such that [tex]\sqrt{2x-6}[/tex] is a real number?
Well if we made 2x-6 as small as possible, ie set it equal to 0, then we can find the answer
[tex]2x-6 = 0\\\\2x = 6\\\\x = 6/2\\\\x = 3\\\\[/tex]
I set the radicand equal to 0 because that's as small as the radicand can get (otherwise, we're dipping into negative territory).
So 2x-6 set equal to 0 leads to x = 3.
This means x = 3 produces the smallest radicand (zero) and therefore, it is the smallest allowed x value for that square root term.
But wait, if we tried x = 3 in f(x), then we get...
[tex]f(x) = \frac{\sqrt{2x-6}}{x-3}\\\\f(3) = \frac{\sqrt{2*3-6}}{3-3}\\\\f(3) = \frac{\sqrt{0}}{0}\\\\[/tex]
which isn't good. We cannot have 0 in the denominator. Dividing by zero is not allowed. The result is undefined. It doesn't even lead to a complex number. So we'll need to bump x = 3 up to x = 4. You should find that x = 4 doesn't make the denominator 0.
----------------
In short, we found that x = 3 makes the square root as small as possible while staying a real number, but it causes a division by zero error with f(x) overall. So we bump up to x = 4 instead.
The true length of recovery for patients with knee surgery is normally distributed with a mean of 123 days and a standard deviation of 1 day. What proportion of the patients will recover between 121 and 124 days?
Answer:
0.81859
Step-by-step explanation:
Given that the length of recovery days for patients with knee surgery is normally distributed with :
Mean, μ = 123 days
Standard deviation, σ = 1 day
The proportion of patients that will recover with 121 and 124 days :
We obtain the Probability of Z score :
Z = (x - μ) / σ
P(Z < (x - μ) / σ) < Z < P(Z < (x - μ) / σ)
P(Z < (121 - 123) / 1) < Z < P(Z < (124 - 123) / 1)
P(Z < - 2) < Z < P(Z < 1)
Using the normal distribution table :
P(Z < 1) - P(Z < - 2)
0.84134 - 0.02275
= 0.81859
Find the length of BC again
Since this is a right triangle, we can use one of the three main trigonometric functions: sine, cosine, or tangent.
Remember: SOH-CAH-TOA
Looking from the angle, we know the opposite side and want to know the adjacent side. Therefore, we should use the tangent function.
tan(61) = 47 / BC
BC = 47 / tan(61)
BC = 26.05 units
Hope this helps!
Answer:
BC = 26.05
Step-by-step explanation:
SOH CAH TOA
tan 61 = 47/BC
BC = 47/tan 61
An article describes an experiment to determine the effectiveness of mushroom compost in removing petroleum contaminants from soil. Out of 155 seeds planted in soil containing 3% mushroom compost by weight, 74 germinated. Out of 155 seeds planted in soil containing 5% mushroom compost by weight, 86 germinated. Can you conclude that the proportion of seeds that germinate differs with the percent of mushroom compost in the soil
Solution :
Let [tex]p_1[/tex] and [tex]p_2[/tex] represents the proportions of the seeds which germinate among the seeds planted in the soil containing [tex]3\%[/tex] and [tex]5\%[/tex] mushroom compost by weight respectively.
To test the null hypothesis [tex]H_0: p_1=p_2[/tex] against the alternate hypothesis [tex]H_1:p_1 \neq p_2[/tex] .
Let [tex]\hat p_1, \hat p_2[/tex] denotes the respective sample proportions and the [tex]n_1, n_2[/tex] represents the sample size respectively.
[tex]$\hat p_1 = \frac{74}{155} = 0.477419[/tex]
[tex]n_1=155[/tex]
[tex]$p_2=\frac{86}{155}=0.554839[/tex]
[tex]n_2=155[/tex]
The test statistic can be written as :
[tex]$z=\frac{(\hat p_1 - \hat p_2)}{\sqrt{\frac{\hat p_1 \times (1-\hat p_1)}{n_1}} + \frac{\hat p_2 \times (1-\hat p_2)}{n_2}}}[/tex]
which under [tex]H_0[/tex] follows the standard normal distribution.
We reject [tex]H_0[/tex] at [tex]0.05[/tex] level of significance, if the P-value [tex]<0.05[/tex] or if [tex]|z_{obs}|>Z_{0.025}[/tex]
Now, the value of the test statistics = -1.368928
The critical value = [tex]\pm 1.959964[/tex]
P-value = [tex]$P(|z|> z_{obs})= 2 \times P(z< -1.367928)$[/tex]
[tex]$=2 \times 0.085667$[/tex]
= 0.171335
Since the p-value > 0.05 and [tex]$|z_{obs}| \ngtr z_{critical} = 1.959964$[/tex], so we fail to reject [tex]H_0[/tex] at [tex]0.05[/tex] level of significance.
Hence we conclude that the two population proportion are not significantly different.
Conclusion :
There is not sufficient evidence to conclude that the [tex]\text{proportion}[/tex] of the seeds that [tex]\text{germinate differs}[/tex] with the percent of the [tex]\text{mushroom compost}[/tex] in the soil.
If two angles are complementary, find the measure of each of angle.
Answer:
B: 30 and 60
Step-by-step explanation:
First, let's set up an equation. Since the two angles are complementary, we can write the equation like this:
2p + p = 90
Now, let's solve it!
2p + p = 90
Combine like terms:
3p = 90
Divide each side by 3 to isolate p:
3p/3 = 90/3
p = 30
Now that we know how many degrees one of our angles is, we can subtract that from 90 to get both of the complementary angles.
90 - 30 = 60
Therefore, the two angles that are complementary in this case are 30 and 60 degrees.
(x - 7)2 = x2 - 49
O True
O False
Answer:
False
Step-by-step explanation:
Twelve different video games showing drug use were observed. The duration times of drug use were recorded, with the times (seconds) listed below. Assume that these sample data are used with a 0.05 significance level in a test of the claim that the population mean is greater than 85 sec. If we want to construct a confidence interval to be used for testing that claim, what confidence level should be used for a confidence interval? If the confidence interval is found to be −1.8 sec<μ<213.5 sec, what should we conclude about the claim? The given confidence interval ▼ does not contain contains the value of 85 sec, so there ▼ is is not sufficient evidence to support the claim that the mean is greater than 85 sec
Answer:
95% confidence level should be used for a confidence interval.
The given confidence interval contains the value of 85 sec, so there is not sufficient evidence to support the claim that the mean is greater than 85 sec.
Step-by-step explanation:
0.05 significance level
1 - 0.05 = 0.95
0.95*100% = 95%
This means that a 95% confidence level should be used for a confidence interval.
Confidence interval is found to be −1.8 sec<μ<213.5 sec, what should we conclude about the claim?
Contains the value of 85 sec, thus there is not sufficient evidence to support the claim that the mean is greater than 85 sec.
Will mark brainliest
Plz solve on a paper or draw on the picture thx in advance
9514 1404 393
Answer:
the red angle has no specific value
Step-by-step explanation:
There is sufficient information here to specify all of the angles except the two unknown angles in the 70° (dark blue) triangle. Those two angles must total 110°, but that measure cannot be allocated between them based on the information in the diagram.
The attachments show that all of the given angle constraints can be met while the red angle may vary considerably. It can range through the interval (0°, 110°), but cannot be either of those end values.
Martha, Lee, Nancy, Paul, and Armando have all been invited to a dinner party. They arrive randomly, and each person arrives at a different time.
a. In how many ways can they arrive?
b. In how many ways can Martha arrive first and Armando last?
c. Find the probability that Martha will arrive first and Armando last.
Show your work
Answer:
a) 120
b) 6
c) 1/20
Step-by-step explanation:
a) 5! = 120
b) (5 - 2)! = 6
c) 6/120 = 1/20
Consider the triangle ΔXYZ . Find the angle Z given that ZY=30 , ZX=15 , and YX=21
Step-by-step explanation:
hey bro can get the diagram
Answer:
where is the diagram plz show the diagram
Step-by-step explanation:
Find the Antilog of 547.840
Answer:
It's impossible because the figure is greater than 10
Step-by-step explanation:
[tex]{ \boxed{ \bf{antilog \: of \: x = \frac{x}{ log} = {10}^{x} }}}[/tex]
Therefore:
[tex]{ \sf{anti(547.840) = {10}^{547.840} }} \\ { \tt{ \red{math \: error \: !}}}[/tex]
Does anyone know the answer??
Answer:
I think the answer is 39x, 13y
Step-by-step explanation:
point : extra points
1 : 3
y : 39
y= 39÷3
y= 13
What is the volume of the following rectangular prism?
Answer:
44/3
Step-by-step explanation:
V=L*W*H
WH=22/3
V=2*(22/3)
When multiplying by 10 how many spaces do you move the decimal point
Answer:
If you multiply a decimal by 10, the decimal point will move one place to the right. If you divide a decimal by 10, the decimal point will move one place to the left.
Step-by-step explanation:
Multiplying a decimal by 10 increases the value of each digit by 10. Multiplying a decimal by a power of 10 increases the value of each digit by a number of times that is equivalent to that power of 10. When a digit's value is changed, that digit is moved to the appropriate place.
convert the following decimals to a simplified fraction. showing all work
Hello.
Answer:
1/200, 667/500
I hoped this helped
OMG!! I’m stuck on 4a) b) c)
Help please
Answer:
a) 750 cmb) 288 cmc) 2112 cmStep-by-step explanation:
Formula for getting the surface area of a rectangular prism: SA = 2 (WL + HL + HW)a) SA = 2 (WL + HL + HW) = 2(75) + 2(225) + 2(75) = 150 + 450 + 150 = 750 cm^2b) SA = 2 (WL + HL + HW)= 2(48) + 2(72) + 2(24)= 96 + 144 + 48=288 cm^2c) SA = 2 (WL + HL + HW)= 2(400) + 2(400) + 2(256)= 800 + 800 + 512= 2112 cm^2[tex]\tt{ \green{P} \orange{s} \red{y} \blue{x} \pink{c} \purple{h} \green{i} e}[/tex]
Answer:
Below in bold.
Step-by-step explanation:
(a) The surface area consists of the sum of the area of 3 sets of 2 congruent rectangles. The 2 rectangles are on opposite sides of the solid.
= 2(15*15) + 2(5*15) + 2(5&15)
= 450 + 150 + 150
= 750 unit^2.
(b). Similarly to the above:
Surface area = 2(12*6) + 2(4*12) + 2(4*6)
= 144 + 96 + 48
= 288 unit^2.
(c) Again:
Surface area = 2(25*16) + 2(25*16) + 2(16*16)
= 400 + 400 + 256
= 1056 unit^2.
find the slope of the line that passes through these two points
Answer:
Step-by-step explanation:
Please help! Identify which of the following is not equivalent to a1/4
Answers (images below)
no links please!
Answer: B
Step-by-step explanation:
A) [tex]a^\frac{3}{4}[/tex]÷[tex]a^\frac{1}{2}[/tex] cannot be the answer. When a to the power of x is divided by a to the power of y it is a to the power of x-y. Ex: [tex]a^x[/tex]÷[tex]a^y=a^x^-^y[/tex]
So 3/4-1/2 is 1/4 giving us [tex]a^{\frac{1}{4} }[/tex]
B is the answer because taking the square root of a is the same as [tex]a^\frac{1}{2}[/tex] which isn't the same as [tex]a^\frac{1}{4}[/tex]
C is not the answer because when a to the power of x is multiplied by a to the power of y it is a to the power of x+y. Ex: [tex]a^x[/tex]·[tex]a^y[/tex]=[tex]a^{x+y}[/tex]
1/8+1/8=1/4 so it is [tex]a^\frac{1}{4}[/tex]
D can't be the answer. [tex]a^\frac{1}{8}[/tex] squared is the same as [tex]a^\frac{1}{8}[/tex]·[tex]a^\frac{1}{8}[/tex] so the same explanation of c applies to d
Alice wants to estimate the percentage of people who plan
on voting yes for the upcoming school levy. She surveys
380 individuals and finds that 260 plan on voting yes.
Identify the values needed to calculate a confidence interval
at the 90% confidence level. Then find the confidence interval.
zo10 z0.05 zo.025 zo01 z0.005
1.282 1.645 1.960 2.326 2.576
Use the table of common z-scores above.
Answer:
"[tex]0.6450 < p < 0.723[/tex]" is the right solution.
Step-by-step explanation:
Given:
n = 380
x = 260
Point estimate,
[tex]\hat p = \frac{x}{n}[/tex]
[tex]=\frac{260}{380}[/tex]
[tex]=0.6842[/tex]
Critical value,
[tex]Zc = 1.645[/tex]
Standard error will be:
[tex]S.E = \sqrt{\frac{0.6842(1-0.6842)}{380} }[/tex]
[tex]=0.0238[/tex]
Margin of error will be:
[tex]E = Zc\times S.E[/tex]
[tex]=1.645\times 0.0238[/tex]
[tex]=0.0392[/tex]
hence,
Confidence level will be:
= [tex]\hat p \pm E[/tex]
= [tex]0.6842 \pm 0.0392[/tex]
= [tex]0.6450 < p < 0.723[/tex]
if 2 shirts cost 18.80, how much would 9 shirt cost.
Answer:
84.60
Step-by-step explanation:
We can write a ratio to solve
18.80 x
--------- = --------------
2 shirts 9 shirts
Using cross products
18.80 *9 = 2x
169.2 =2x
Divide each side by 2
169.2/2 =2x/2
84.60 =x
Find the face value of the 20-year zero-coupon bond at 4.4%, compounded semiannually, with a price of $8,375.
$45.000
$53.000
The correct face value will be Option C ($20,000). A further solution id provided below.
Given:
Time,
t = 20 years
Rate,
r = 4.4%
Price
= $8,375
Now,
The yield will be:
= [tex]\frac{4.4}{2}[/tex]
= [tex]1.1[/tex] (%)
Time will be:
= [tex]20\times 2[/tex]
= [tex]40 \ periods[/tex]
As we know the formula,
⇒ [tex]Price \ of \ bond = \frac{Face \ value}{(1+\frac{r}{2} )^{n\times 2}}[/tex]
By substituting the values, we get
[tex]8375=\frac{Face \ value}{(1+\frac{0.044}{2} )^{20\times 2}}[/tex]
[tex]8375=\frac{Face \ value}{(1.022)^{40}}[/tex]
[tex]8375=\frac{Face \ value}{2.3880083}[/tex]
The face value will be:
[tex]Face \ value = 2.3880083\times 8375[/tex]
[tex]=20,000[/tex] ($)
Learn more about face value here:
https://brainly.com/question/14862802
Suppose taxi fares from Logan Airport to downtown Boston is known to be normally distributed and a sample of seven taxi fares produces a mean fare of $21.51 and a 95% confidence interval of [$20.52, $22.48]. Which of the following statements is a valid interpretation of the confidence interval?
a. we are 95% confident that a randomly selected taxi fare will be between $2051 and $2421.
b. 95% of all taxi fares are between $2051 and $2421.
c. We are 95% confident that the average tau fare between Logan Airport and downtown Boston will fall between $2051 and $2421.
d. The mean amount of a taxi fare is $22.31, 95% of the time.
Answer:
c. We are 95% confident that the average taxi fare between Logan Airport and downtown Boston will fall between $20.51 and $24.21.
Step-by-step explanation:
x% confidence interval:
A confidence interval is built from a sample, has bounds a and b, and has a confidence level of x%. It means that we are x% confident that the population mean is between a and b.
95% confidence interval of [$20.52, $22.48].
We can be 95% sure that the true mean amount of taxis fares in downtown Boston is in this interval, and thus, the correct answer is given by option C.
The number of basic trigonometric ratios is....
A.3
B.4
C.5
D.6
Answer:
There are three basic trigonometric ratios: sine , cosine , and tangent .
Step-by-step explanation:
Please help! I will give you a lot of points if you do and the brainiest!
Answer:
First truth table:
~q p V ~q ~(p V ~q)
F T F
T T F
F F T
T T F
Second truth table:
~q p V ~q ~(p V ~q)
F T F
Step-by-step explanation:
The ~ operator is a negator (or NOT), such that it is the opposite of the sign.
The first column wants the negation of [tex]q[/tex], and the values of q are
T, F, T, F, for the columns starting from the top. The negation for the columns are F, T, F, T.
For the second column, The 'V' operator is the OR operator, so a single True, or T will result in a True.
For the first row, not q is F, and T OR F will result in T.
For the second row, not q is T, and T OR T will result in T.
For the third row, not q is F, and F OR F will result in F.
For the fourth row, not q is T, and F OR T will result in T.
In the last column, we must figure out not p OR not q, which we did in the last column, so all we must do is figure out the NOT of values of the last column.
The values of the last column are T, T, F, T, respectively, so the not of the columns will be F, F, T, F.
In the bottom truth table, not q, will be F because the value of q is T. The second column wants p OR not q, and we already know that not q is F, and the value of p is T. T OR F is equal to T. In the last column, the question wants the not of p OR not q, which we did in the last column, so we must figure out the not value of the last column, which is T. The not of T is F.
Select the correct answer.
What is the value of this expression when x = -6 and ?
4(x2 + 3) − 2y
Answer:
D. 157
Step-by-step explanation:
4(x^2+3)-2y
4(6^2+3)-2(-1/2) add in given values
4(39)+1. start with parentheses
156+1. combine like terms
157. answer
Answer:
D. 157
Step-by-step explanation:
Hi there!
We want to find the value of the expression 4(x²+3)-2y is when x=-6 and y=-1/2
Let's first simplify the expression, as that will likely make it easier
Distribute 4 to both x² and 3
4x²+12-2y
That's the expression
Substitute -6 as x into the expression
4(-6)²+12-2y
Raise (-6) to the second power
4*36+12-2y
Multiply 36 by 4
144+12-2y
Add 12 and 144 together
156-2y
Now the expression is 156-2y
But remember that we know that y=-1/2, and we haven't substituted it into the expression yet
Substitute -1/2 as y into the expression
156-2(-1/2)
Multiply
156+2/2
Simplify
156+1
Add
157
Hope this helps!
A boat is pulled into a dock by means of a winch 12 feet above the deck of the boat. (a) The winch pulls in rope at a rate of 4 feet per second. Determine the speed of the boat when there is 15 feet of rope out.
Answer:
the speed of the boat is 6.67 ft/s
Step-by-step explanation:
Given;
height of the winch, h = 12 ft
the rate at which the winch pulls, the rope, = 4 ft/s
This form a right triangle problem;
let the height of the right triangle = h
let the base of the triangle = b (this corresponds to the horizontal displacement of the boat)
let the hypotenuse side = c
c² = b² + h²
[tex]2c\frac{dc}{dt} = 2b\frac{db}{dt} + 2h \frac{dh}{dt}\\\\The \ height \ of \ the \ winch \ is \ not \ changing \\\\2c\frac{dc}{dt} = 2b\frac{db}{dt} + 2h (0)\\\\2c\frac{dc}{dt} = 2b\frac{db}{dt} \\\\c\frac{dc}{dt} = b\frac{db}{dt} ----(*) \\\\when;\\\\the\ hypotenuse \ c = 15 \ ft\\\\the \ the \ the \ height, h = 12 \ ft\\\\the \ base, b \ becomes ;\\\\b^2 = c^2 -h^2\\\\b^2 = 15^2 - 12^2\\\\b^2 = 81\\\\b = \sqrt{81} \\\\b = 9 \ ft\\\\\\from \ the \ equation (*) \ above;\\\\[/tex]
[tex]c\frac{dc}{dt} = b \frac{db}{dt} \\\\dc/dt = 4 \ ft/s, \ \ c = 15 \ ft, \ \ b = 9 \ ft\\\\15 (4) = 9\frac{db}{dt} \\\\60 = 9 \frac{db}{dt} \\\\\frac{db}{dt} = \frac{60}{9} = 6.67 \ ft/s[/tex]
Therefore, the speed of the boat is 6.67 ft/s
An office manager has received a report from a consultant that includes a section on equipment replacement. The report indicates that scanners have a service life that is normally distributed with a mean of 41 months and a standard deviation of 4 months. On the basis of this information, determine the proportion of scanners that can be expected to fail within plus or minus 6 months of the mean. (Enter your answer as a percentage without the percent sign; keep 2 decimal places)
Answer:
The answer is "36.14%"
Step-by-step explanation:
The complete question is given in the attached file please find it.
[tex]\mu =41\\\\\sigma= 4\\\\P(42<\bar{x}<48)= p(\bar{x}<48)-p(\bar{x}<42)\\\\Z =\frac{(42-41)}{4} = \frac{1}{4} =0.25\\\\Z =\frac{(48-41)}{4} = \frac{7}{4} = 1.75\\\\[/tex]
Using z-table to find the value.
[tex]\to P(41<\bar{x}<48) = 0.9599- 0.5987 = 0.3614\times 100= 36.14\%[/tex]
This means that between 42 and 48 months, 36.14 % of scanners could be predicted will break down.
The answer to this math problem need help
Step-by-step explanation:
you know that you can copy and paste and give the answer
