Here, I've attached a picture of the triangle that accompanies this explanation.
cot = = =
Now view the triangle.
PS. Angle theta will have a coordinate of (-, +) because it is in quadrant II.
sin of the angle would be opposite/hypotenuse, so sin =
cos of the angle would be adjacent/hypotenuse, so cos =
tan of the angle would be opposite/adjacent, so tan =
Answer:
And we can find this probability using the normal standard table or excel:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the amount of ml of a population, and for this case we know the distribution for X is given by:
Where 
and 
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability using the normal standard table or excel:
The diameter of the new rubber ball, to the nearest foot, must be D = 4.0 ft (in the case of the maximum cost).
<h3>
How to find the diameter of the ball?</h3>
Remember that for a sphere of diameter D, the surface area is:
A = 4*pi*(D/2)^2
In this case, the cost is $0.02 per square foot, and the company wants to expend (at maximum) $1 per ball, so first we need to solve:
$0.02*A = $1
A = $1/$0.02 = 50
So the surface of the ball must be 50 square feet.
Then we solve:
50ft^2 = 4*3.14*(D/2)^2
D = 2*√(50 ft^2/(4*3.14)) = 4.0 ft
If you want to learn more about spheres, you can read:
brainly.com/question/10171109
Answer:
x² + y² = 85
Step-by-step explanation:
Using the expansion
(x - y)² = x² + y² - 2xy , then
x² + y² - 2xy = (x - y)² ( add 2xy to both sides )
x² + y² = (x - y)² + 2xy ← substitute given values
= 9² + 2(2)
= 81 + 4
= 85
