Answer:
D. 3/19
Step-by-step explanation:
12/1 = 12
12/2 = 6
12/3 = 4
These are the only ones that make the equation true.
There are also only 19 numbers because they need to be less than 20 like the question indicated. Therefore, the answer is D.
(-9x²-2x) - (-9x²-3x) = (-9x²-2x) +(9x²+3x) = -9x²-2x+9x²+3x = (-9x²+9x²)+(-2x+3x) = x
Answer:
∫▒〖arctan(x).1 dx=arctan(x).x〗-1/2 ln(1+x^2 )+C
Step-by-step explanation:
∫▒〖1st .2nd dx=1st∫▒〖2nd dx〗-∫▒〖(derivative of 1st) dx∫▒〖2nd dx〗〗〗
Let 1st=arctan(x)
And 2nd=1
∫▒〖arctan(x).1 dx=arctan(x) ∫▒〖1 dx〗-∫▒〖(derivative of arctan(x))dx∫▒〖1 dx〗〗〗
As we know that
derivative of arctan(x)=1/(1+x^2 )
∫▒〖1 dx〗=x
So
∫▒〖arctan(x).1 dx=arctan(x).x〗-∫▒〖(1/(1+x^2 ))dx.x〗…………Eq1
Let’s solve ∫▒(1/(1+x^2 ))dx by substitution now
Let 1+x^2=u
du=2xdx
Multiply and divide ∫▒〖(1/(1+x^2 ))dx.x〗 by 2 we get
1/2 ∫▒〖(2/(1+x^2 ))dx.x〗=1/2 ∫▒(2xdx/u)
1/2 ∫▒(2xdx/u) =1/2 ∫▒(du/u)
1/2 ∫▒(2xdx/u) =1/2 ln(u)+C
1/2 ∫▒(2xdx/u) =1/2 ln(1+x^2 )+C
Putting values in Eq1 we get
∫▒〖arctan(x).1 dx=arctan(x).x〗-1/2 ln(1+x^2 )+C (required soultion)
The average speed, in km/minute, of the train is 2.79 km/minute
<h3>Calculating average speed </h3>
From the question, we are to calculate the average speed in km/minute
From the given information,
Distance travelled = 503 km
Time taken = 3 hours = 3 × 60 minutes = 180 minutes
Using the average speed formula,
Average speed = Distance / Time
∴ Average speed of the train = 503 / 180
Average speed of the train = 2.79 km/minute
Hence, the average speed, in km/minute, of the train is 2.79 km/minute
Learn more on Calculating average speed here: brainly.com/question/12025128
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Answer:
6 5/6
Step-by-step explanation:
diameter is radius multiplied by 2
* means multiplied by
3 5/12 = 41/12
41/12 * 2 = 82/12 = 6 5/6
