Recall the angle sum identity for cosine,
cos(α + β) = cos(α) cos(β) - sin(α) sin(β)
Then given sin(α) = -1/3, we have
cos(α + β) = cos(α) cos(β) + 1/3 sin(β)
α is in quadrant IV, so 3π/2 < α < 2π, and so sin(α) is negative and cos(α) is positive. Then from the Pythagorean identity, we get
sin²(α) + cos²(α) = 1
⇒ cos(α) = √(1 - sin²(α)) = 2√2/3
β is in quadrant III, so π < β < 3π/2, so both sin(β) and cos(β) are negative. If we multiply both sides of the previous identity by 1/cos²(α) and replace α with β, we get
sin²(β)/cos²(β) + cos²(β)/cos²(β) = 1/cos²(β)
⇒ tan²(β) + 1 = 1/cos²(β)
⇒ 1/cos(β) = -√(tan²(β) + 1) = -√58/3
⇒ cos(β) = -3/√58
Also recall that by definition,
tan(β) = sin(β)/cos(β)
⇒ sin(β) = tan(β) cos(β) = 7/3 • (-3/√58) = -7/√58
Putting everything together, we find that
cos(α + β) = 2√2/3 • (-3/√58) + 1/3 • (-7/√58) = -(6√2 + 7)/(3√58)
or more clearly,
[tex]\cos(\alpha + \beta) = -\dfrac{6\sqrt2 + 7}{3\sqrt{58}}[/tex]
The 1st one was doable, but I don't understand the 2nd Question.
Answer: ? What are you talking about?
Step-by-step explanation:
Given f(x)=-x-4f(x)=−x−4, find f(4)f(4).
Answer:
1/4 or .25
Explanation
As for this specific question algebra is something I do in my head and skip many steps for however if you want to proof my answer it would be this.
-0.25-16*.25=-0.25-4
-0.25-4=-0.25-4
-4.25=-4.25
For the function f(x) = -x-4 the value of f(4) is -8.
The given function is f(x) = -x-4.
We need to find the value of f(4).
To find this we have to replace the x value with 4.
Substitute x=4 in the function:
f(4)=-4-4
f(4)=-8
Hence, the value of f(4) is -8.
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Find the surface area of the square pyramid below.
Answer:
Step-by-step explanation:
Answer:
96 cm or B
Step-by-step explanation:
Base-l*w, 6*6, 36
Side 1-(h*w)1/2, (30)1/2, 15
Side 2-Same as 1
Side 3-Same as 1
Side 4-Same as 1
15+15=30, 15+15=30, 30+30=60, 60+36=96
96 cm
Please help with this question
Answer:
The question or equation is not clear.....
Class 10R sat a test.
The mean mark for the class was 70%.
There are 30 students in class 10R, 20 of whom are boys.
The mean mark for the boys in the test was 62%.
Work out the mean mark for the girls.
86%
Step-by-step explanation:30 students in the class with a mean average of 70% can be expressed as:
total class percent / 30 = 70%
Rearranged, this gives that the class achieved a total of 30x70 or 2100%.
20 boys in the class with a mean average of 62% can be expressed as:
total boys percent / 20 = 62%
Rearranged, this gives that the boys achieved a total of 20x62 or 1240%.
This means that the girls achieved 2100 - 1240 so 860%.
Because there are 30 students and 20 boys, there are 10 girls.
Then work out the mean with a total of 860% and 10 girls.
860/10 = 86%.
Express in vertex form
Y=2x^2 - 2x - 5
Answer:
y = 2(x - [tex]\frac{1}{2}[/tex] )² - [tex]\frac{11}{2}[/tex]
Step-by-step explanation:
y = 2x² - 2x - 5 ← factor out 2 from the first 2 terms
= 2(x² - x) - 5
Using the method of completing the square
add/subtract (half the coefficient of the x- term)² to x² - x
y = 2(x² + 2(- [tex]\frac{1}{2}[/tex] ) x + [tex]\frac{1}{4}[/tex] - [tex]\frac{1}{4}[/tex] ) - 5
= 2(x - [tex]\frac{1}{2}[/tex] )² + 2(- [tex]\frac{1}{4}[/tex] ) - 5
= 2(x - [tex]\frac{1}{2}[/tex] )² - [tex]\frac{1}{2}[/tex] - 5
= 2(x - [tex]\frac{1}{2}[/tex] )² - [tex]\frac{11}{2}[/tex] ← in vertex form
pls help fast
brainlest to enyone who helps
Answer:
B STEP 2
Step-by-step explanation:
5/8 is not more than 1
A Distributive Property and GCF
56+42
Answer:
98
Step-by-step explanation:
you at 56 in to 42
Answer:
98
pa brainless
Step-by-step explanation:
please brainless
Use a calculator . Round to the nearest tenth of a degree given cos 0=0.8458
0.8458 rounded to the nearest tenth is 0.8 given cos is 0.696706709347
Question 13 of 20
If fx) = 5x- 4 and g(x) = 4x+1, find (f- g)(x).
Answer:
Step-by-step explanation:
x-5
Which of the following sets of ordered pairs is not a function?
{(-1, 2), (1, 3), (1, 5), (-3, 4)}
{(0, 2), (1, 4), (2, 5), (3, 6)}
{(-4, 3), (-1, 1), (-2, 5), (3, 7)}
{(0, 2), (1, 2), (2, 2), (3, 2)}
Answer:
1
first choice
Step-by-step explanation:
in a function, the x-value never repeats.
(found in brainly)
help please i need it
Answer:
42m + 12
Step-by-step explanation:
6 ( 7m + 2 )
= 6 ( 7m ) + 6 ( 2 )
= ( 6 * 7m ) + ( 6 * 2 )
= 42m + 12
Answer:
a
Step-by-step explanation:
do distributive property and u get 42m+12
the shown bellow question answer
Answer:
The area of the shape can be divided into the area of the rectangle, and the area of the semi-circle.
The area of the rectangle can be found by [tex]11*4=44[/tex]
The area of a semi-circle can be found with the formula [tex]\frac{1}{2} \pi r^2[/tex] where r is the radius.
Since we know the diameter of the semi-circle is 4,
the radius will be 4 ÷ 2 = 2.
Therefore, the area of the semi-circle is [tex]\frac{1}{2}\pi 2^2=\frac{1}{2}\pi*4=2\pi[/tex]
Therefore, the area of the shape is [tex]44+2\pi[/tex] or [tex]50.283cm^2[/tex] (3 decimal places)
combine like terms and solve x
12x + 3 - 4x - 6 = 5
5x - 4 + 7 + 6x - 4x = 24
Answer:
12x + 3 - 4x - 6 = 5
x=1
5x - 4 + 7 + 6x - 4x = 24
x=3
i need the answer for
3-3 Mini Assessment | Constant of Proportionality in Graphs
Question
POSSIBLE POINTS: 1
The relationship between the number of ounces of tea purchased and the total cost of the tea is proportional as shown in the graph.
Which equation models this relationship?
y = 7/4x
y = 4/7x
y = 4/1x
y = 1/4x
Answer: y= (7/4)x
Step-by-step explanation:
Build a table of representative values and then calculate the slope between any 2 of the points. I'll pick (2,3.5) and (8,14) [See attachment. ]
The slope is the Rise/Run:
Rise = (14 - 3.5) = 10.5
Run = (8-2) = 6
Slope = Rise/Run: (10.5/6) = 1.75
The equation should read y = 1.75x.
None of the options works, as written, but note that 7/4 looks close to 1.75. In fact, 7/4 = 1.75.
Use the equation y = 1.75x and enter several values of x (the ounces purchased) and y (the total cost of the purchase). The attachment summarizes the results (Predicted), along with the actual values (Actual) taken from the graph. Excellent correlation, considering the difficulty in making precise graph readings.
Therefore y = (7/4)x
evaluate x-2y when x =0.75 and y =0.96
Step-by-step explanation:
x = 0,75
y = 0,96
= x - 2y
= 0,75 - 2.0,96
= 0,75 - 1,96
= -1,21
A researcher wants to estimate the likelihood that the baseball player will hit 2 home runs in a single game, given that the player hits a home run once in every 13 times at bat. Which type of study is most suitable for data collection in this situation?
A. experimental
B. census
C. survey
D. simulation
Consider an economy made up of 100 people, 50 of whom hold jobs, 10 of whom are
looking for work, and 15 of whom are retired. The unemployment rate is approximately:
17 percent
10 percent
25 percent
20 percent
12 percent
Answer:
20 por cento de cada um , que colocar
The unemployment rate is approximately 17 per cent. The correct option is A.
To calculate the unemployment rate, we need to consider the number of unemployed individuals (those looking for work) divided by the total labour force (those employed plus those looking for work).
Given:
Total population = 100
Employed individuals = 50
Individuals looking for work (unemployed) = 10
Total labour force = Employed + Unemployed
Total labor force = 50 + 10 = 60
Unemployment rate = (Unemployed / Total labour force) x 100
Unemployment rate = (10 / 60) x 100 ≈ 16.67 percent
Rounding to the nearest whole number, the unemployment rate is approximately 17 per cent.
Therefore, the correct answer is option A.
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Which numbers are solutions to the equation 30=x2?
If you meant 2x, x is 15; if you meant x^2, the answer is the square root of 30
Express 2x2 + 16x +11 in the form a (x + b)2 + c, where a, b and c are
numbers.
What are the values of a, b and c?
Step-by-step explanation:
I assume the original expression is
2x² + 16x + 11
we need to get this into the form of a(x + b)² + c
let's do the generic multiplication and compare the result to the given expression :
a(x² + 2bx + b²) + c = ax² + 2abx + ab² + c
when we compare this with the original equation, we only need to look at terms with the same variable exponents.
2x² is the only term with "x²".
and ax² is the only term with "x²" in the generic form.
so ?
2x² = ax²
=>
a = 2
16x is the only term with "x" (exponent 1).
2abx is the only term with "x" in the generic form.
16x = 2abx
8x = abx = 2bx
4x = bx
=>
b = 4
11 is the only pure number (constant).
ab² + c is the only constant term in the genetic form.
11 = ab² + c = 2×4² + c = 2×16 + c = 32 + c
-21 = c
so, the solution is
2(x + 4)² - 21
pls help ill give brainliest
Answer:
4
Step-by-step explanation:
-5g -6
Let g= -2
-5 (-2) -6
Multiply
10 -6
4
Answer:
A. 4
Step-by-step explanation:
So, we have an equation with a variable (g), and they've given us the value of g to be -2. All we have to do at this stage is plug in the value of g into the equation.
-5g-6 (g=-2)
-5(-2)-6
10-6=4
Doing the math by plugging in -2, you would get your answer to be 4. Let me know if you see any errors, and if you have any further questions at all.
Draw an ordered stem and leaf diagram to show this information.
245, 250, 251, 253, 258, 264, 267, 269, 273, 276
Key:24|5 means 245.
=========================================================
Explanation:
The key tells us how to set up the stem and leaf diagram. It says that [tex]24|5[/tex] represents the value 245.
This means that "24" is one of the stems. In fact, it's the smallest stem possible since there's nothing smaller than 240 on this given list of values.
The only leaf associated with this stem is 5. The stem 24 and the leaf 5 combine to form the number 245 as the key indicates.
--------------------------
In the next row is the stem 25. For this stem, we'll have the leaves of: 0, 1, 3, 8. The stem 25 and those leaves mentioned combine to form 250, 251, 253, 258 in that exact order. This time we'll use up four boxes for this row. The last box in this row is blank.
The remaining rows (stems 26 and 27) are handled in pretty much the same fashion. Let me know if you have questions how the boxes are filled in. It helps to start with sorted data from smallest to largest. Luckily, that's already been done for us.
The filled out chart is shown below. I replaced the stems 0,1,2,3 with 24,25,26,27.
tim gtri nguyen cua x de bthuc B=x+2/can(x) - 1
Answer:
sorry di ko alam
Step-by-step explanation:
1.what is the y-intercept f (x) = 3x+8/x-4?
a.-2
b.0
c.2
d.4
2.the horizontal asymptote of f (x) = 2x+5/x^2-3x+2?
a. y = -1
b. y = 0
c. y = 1
d. y = 2
3. what is the x - intercept of f (x) = 2x+6/x-1?
a.-5
b.-3
c.-1
d.0
4.what is the vertical asymptote of f (x) = x^2+5x+6/x-5?
a.x = -6
b.x = 0
c.x = 5
d.x = 6
5. what is the zero of f (x) = x^2-25/x+5?
a.-5
b.0
c.5
d.25
6.the oblique asymptote of f (x) = x^2=3x-5/x+2?
a.y = x + 1
b.y = x + 2
c.y = x + 3
d.y = x + 5
The Eubanks Answer:
Step-by-step explanation:hehus
7⅕-2⅔x0,5 explain step by step
Step-by-step explanation:
7/5 - 2×2/3 × 0.5 = 1.4 - 2×0.5×2/3
= 1.4 - 1 ×2/3
=1/4 × 2/3
=1.5 - 0.6
line j passes through the point (-4,10) and (2,-8). Line k passes through the point (1,2) and is parallel to line j. Find an equation for line k.
Answer:
344444444433333338694
Step-by-step explanation:
Answer: y = -3x+5
Step-by-step explanation:
7 6/10= ?/? please help
Answer:
7.6
Step-by-step explanation:
Answer:
76/10
Explanation
7 × 10 is 70 + the 6 is 76/10
you can look up fractions on yt
to get a better explication.
What are the roots of the equation 4x^2+24x+45=0 in simplest a+bi form?
Answer:
X=(-1.5, 7.5)
Step-by-step explanation:
Simplifying
4x2 + -24x + -45 = 0
Reorder the terms:
-45 + -24x + 4x2 = 0
Solving
-45 + -24x + 4x2 = 0
Solving for variable 'x'.
Factor a trinomial.
(-3 + -2x)(15 + -2x) = 0
Set the factor '(-3 + -2x)' equal to zero and attempt to solve:
Simplifying
-3 + -2x = 0
Solving
-3 + -2x = 0
Move all terms containing x to the left, all other terms to the right.
Add '3' to each side of the equation.
-3 + 3 + -2x = 0 + 3
Combine like terms: -3 + 3 = 0
0 + -2x = 0 + 3
-2x = 0 + 3
Combine like terms: 0 + 3 = 3
-2x = 3
Divide each side by '-2'.
x = -1.5
Simplifying
x = -1.5
Set the factor '(15 + -2x)' equal to zero and attempt to solve:
Simplifying
15 + -2x = 0
Solving
15 + -2x = 0
Move all terms containing x to the left, all other terms to the right.
Add '-15' to each side of the equation.
15 + -15 + -2x = 0 + -15
Combine like terms: 15 + -15 = 0
0 + -2x = 0 + -15
-2x = 0 + -15
Combine like terms: 0 + -15 = -15
-2x = -15
Divide each side by '-2'.
x = 7.5
Simplifying
x = 7.5
Solution
x = {-1.5, 7.5}
Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score
of a man 72.4 inches tall. (to 2 decimal places)
Work Shown:
z = (x - mu)/sigma
z = (72.4 - 69.0)/(2.8)
z = (3.4)/(2.8)
z = 1.2142857 .... which is approximate
z = 1.21
Z-score of a man who is 72.4 inches tall is 0.45.
Understanding the concept of the z-score helps us gauge how far a value is from the mean in terms of standard deviations.
A z-score, denoted as , measures the deviation of a data point from the mean in terms of standard deviations. It's calculated using the formula:
= ( - ) /
Where:
- is the value we want to find the z-score for (72.4 inches in this case).
- is the mean of the dataset (69.0 inches).
- is the standard deviation of the dataset (2.8 inches).
Plugging in the values:
= (72.4 - 69.0) / 2.8 = 1.25 / 2.8 ≈ 0.446
Rounded to two decimal places, the z-score is approximately 0.45.
This means that a man who is 72.4 inches tall is roughly 0.45 standard deviations above the mean height of adult men.
In other words, his height is a bit taller than the average height by about 0.45 times the standard deviation.
This positive value indicates that the man's height is above the mean. If the z-score were negative, it would mean the height is below the mean. By using z-scores, we can compare data points from different distributions and understand how unusual or typical a particular value is within its dataset.
Z-scores help us quantify the relative position of a data point, providing a standardized way to interpret its significance in the context of the dataset's characteristics.
In summary, the z-score of a man who is 72.4 inches tall is approximately 0.45, indicating that his height is slightly above the average height of adult men.
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what is 916 divied by 320
Answer:
2.8625
This is 916 divided by 320
Answer:
Full Answer - 2.8625
Rounded - About 3
Nearest Tenth - 2.9
Nearest Hundredth - 2.86
Step by Step:
Shown Below
Hope this Helps
