Firstly, solve 38C15.
Then solve 42C12.
Compare your answers.
The goal here is to see if 38C15 = 42C12.
Here is the formula:
nCr = n!/(r!(n - r)!
Go for it.
Answer:
(-1/2, 3/4)
Step-by-step explanation:
Let's use the elimination by adding or subtracting method. Note that we have 8y in the first equation, and that we could obtain -8y in the second equation by multiplying the second equation by 2:
2(24x - 4y = -15) => 48x - 8y = -30
Now combine this result (this equation) with the first equation:
2x + 8y = 5
+48x -8y = -30
---------------------
50x = - 25
Dividing both sides by 50, to isolate x, we get
x = -25/50 = -1/2.
Now substitute -1/2 for x in the first equation and solve the resulting equation for y:
2x + 8y = 5
2(-1/2) + 8y = 5, or -1 + 8y = 5, or 8y = 6 (after having added 1 to both sides)
Dividing both sides of 8y = 6 by 8 leads to determining the value of y:
y = 6/8 = 3/4
The solution is (-1/2, 3/4).
A) Demand function
price (x) demand (D(x))
4 540
3.50 810
D - 540 810 - 540
----------- = -----------------
x - 4 3.50 - 4
D - 540
----------- = - 540
x - 4
D - 540 = - 540(x - 4)
D = -540x + 2160 + 540
D = 2700 - 540x
D(x) = 2700 - 540x
Revenue function, R(x)
R(x) = price * demand = x * D(x)
R(x) = x* (2700 - 540x) = 2700x - 540x^2
b) Profit, P(x)
profit = revenue - cost
P(x) = R(x) - 30
P(x) = [2700x - 540x^2] - 30
P(x) = 2700x - 540x^2 - 30
Largest possible profit => vertex of the parabola
vertex of 2700x - 540x^2 - 30
When you calculate the vertex you find x = 5 /2
=> P(x) = 3345
Answer: you should charge a log-on fee of $2.5 to have the largest profit, which is $3345.
Answer:
cos B = 
tan B = 
sin B = 
Step-by-step explanation:
In the right triangle, there are three sides and 2 acute angles
- Hypotenuse ⇒ the opposite side of the right angle
- Leg1 and Leg 2 ⇒ the sides of the right angle
The trigonometry functions of one of the acute angles Ф are
- sin Ф = opposite leg/hypotenuse
- cos Ф = adjacent leg/hypotenuse
- tan Ф = opposite leg/adjacent leg
In Δ ACB
∵ ∠C is the right angle
∴ AB is the hypotenuse
∵ AC is the opposite side of ∠B ⇒ leg1
∵ CB is the adjacent side of ∠B ⇒ leg2
→ By using the ratios above
∴ cos B = 
, tan B = 
, sin B = 
∵ CB = 7, AB = 25, AC = 24
∴ cos B =
∴ tan B =
∴ sin B =
<span>Length = l</span>
<span>
Width = w</span>
<span>
Perimeter = p = 100
</span>
<span>Perimeter of rectangle = 2(l+w)</span>
<span>
100 = 2 (4w + w)</span>
<span>
100 = 2(5w)</span>
<span>
100 = 10w</span>
<span>
100/10 = w</span>
<span>
10 = w</span>
<span>
w = 10
Area of rectangle = length * width</span>
<span>
a = l*w</span>
<span>
a = 4w*w</span>
<span>
a = 4w^2............(1)</span>
<span>
Put the value of w in (1)</span>
<span>
a = 4(10)^2</span>
<span>
a= 4(100)</span>
<span>
a = 400 yd^2</span>
