Answer:
Step-by-step explanation:
<u>Sum of interior angles of a polygon:</u>
- (n - 2)180 = 160n
- 180n - 360 = 160n
- 20n = 360
- n = 18
This is quite a complex problem. I wrote out a really nice solution but I can't work out how to put it on the website as the app is very poorly made. Still, I'll just have to type it all in...
Okay so you need to use a technique called logarithmic differentiation. It seems quite unnatural to start with but the result is very impressive.
Let y = (x+8)^(3x)
Take the natural log of both sides:
ln(y) = ln((x+8)^(3x))
By laws of logarithms, this can be rearranged:
ln(y) = 3xln(x+8)
Next, differentiate both sides. By implicit differentiation:
d/dx(ln(y)) = 1/y dy/dx
The right hand side is harder to differentiate. Using the substitution u = 3x and v = ln(x+8):
d/dx(3xln(x+8)) = d/dx(uv)
du/dx = 3
Finding dv/dx is harder, and involves the chain rule. Let a = x+ 8:
v = ln(a)
da/dx = 1
dv/da = 1/a
By chain rule:
dv/dx = dv/da * da/dx = 1/a = 1/(x+8)
Finally, use the product rule:
d/dx(uv) = u * dv/dx + v * du/dx = 3x/(x+8) + 3ln(x+8)
This overall produces the equation:
1/y * dy/dx = 3x/(x+8) + 3ln(x+8)
We want to solve for dy/dx, achievable by multiplying both sides by y:
dy/dx = y(3x/(x+8) + 3ln(x+8))
Since we know y = (x+8)^(3x):
dy/dx = ((x+8)^(3x))(3x/(x+8) + 3ln(x+8))
Neatening this up a bit, we factorise out 3/(x+8):
dy/dx = (3(x+8)^(3x-1))(x + (x+8)ln(x+8))
Well wasn't that a marathon? It's a nightmare typing that in, I hope you can follow all the steps.
I hope this helped you :)
Answer:
Increase
Step-by-step explanation:
The researcher records the following estimates: 450, 426, 310, 500, and 220.
The mean of these estimates is derived below.
Mean = (450+426+310+500+220)/5
=1906/5=381.2
If the researcher removes the estimate of 220.
The mean of the other numbers will be:
Mean =(450+426+310+500)/4
=1686/4=421.5
By comparison of the two mean, we can see that the value of the mean will increase.
Answer:
d) 1/2 ÷ 4 = 1/2 • 4/1
Step-by-step explanation:
when dividing fractions use keep change flip (keep the first fraction, change the sign to multiplication, flip the second fraction)
when multiplying just multiply straight across
