Answer:
640
Step-by-step explanation:
you say 100% = 800
what about 80%(i get 80% after substracting 100% that's marked price - 20% discount)
then u say 80×800÷100
Answer:
third option
Step-by-step explanation:
four times a number: 4n
add 8 to it: 4n + 8
All of this equals to -12.
Hence: 4n + 8 = -12
First, we have to convert our function (of x) into a function of y (we revolve the curve around the y-axis). So:

And the derivative of x:

Now, we can calculate the area of the surface:

We could calculate this integral (not very hard, but long), or use
(1),
(2) and
(3) to get:



Calculate indefinite integral:

And the area:
![A=2\pi\int\limits_0^{10}x\sqrt{4x^2+1}\,dx=2\pi\cdot\dfrac{1}{12}\bigg[\left(4x^2+1\right)^\frac{3}{2}\bigg]_0^{10}=\\\\\\= \dfrac{\pi}{6}\left[\big(4\cdot10^2+1\big)^\frac{3}{2}-\big(4\cdot0^2+1\big)^\frac{3}{2}\right]=\dfrac{\pi}{6}\Big(\big401^\frac{3}{2}-1^\frac{3}{2}\Big)=\boxed{\dfrac{401^\frac{3}{2}-1}{6}\pi}](https://tex.z-dn.net/?f=A%3D2%5Cpi%5Cint%5Climits_0%5E%7B10%7Dx%5Csqrt%7B4x%5E2%2B1%7D%5C%2Cdx%3D2%5Cpi%5Ccdot%5Cdfrac%7B1%7D%7B12%7D%5Cbigg%5B%5Cleft%284x%5E2%2B1%5Cright%29%5E%5Cfrac%7B3%7D%7B2%7D%5Cbigg%5D_0%5E%7B10%7D%3D%5C%5C%5C%5C%5C%5C%3D%20%5Cdfrac%7B%5Cpi%7D%7B6%7D%5Cleft%5B%5Cbig%284%5Ccdot10%5E2%2B1%5Cbig%29%5E%5Cfrac%7B3%7D%7B2%7D-%5Cbig%284%5Ccdot0%5E2%2B1%5Cbig%29%5E%5Cfrac%7B3%7D%7B2%7D%5Cright%5D%3D%5Cdfrac%7B%5Cpi%7D%7B6%7D%5CBig%28%5Cbig401%5E%5Cfrac%7B3%7D%7B2%7D-1%5E%5Cfrac%7B3%7D%7B2%7D%5CBig%29%3D%5Cboxed%7B%5Cdfrac%7B401%5E%5Cfrac%7B3%7D%7B2%7D-1%7D%7B6%7D%5Cpi%7D)
Answer D.
Answer:
-2x³ - 2y² + z⁴
Step-by-step explanation:
Step 1: Write out expression
x³ - 2y² - 3x³ + z⁴
Step 2: Combine like terms (x³)
-2x³ - 2y² + z⁴
Answer:
On Wednesday
Step-by-step explanation:
In this question, We have Alana practicing for three days. We now need to know in which of the days has she practiced closest to 2 hours. Hence, what we are to do here is simply find which of the practicing hours is nearest to 2hours.
The best thing to do here is to work with minutes. Hence whatsoever fraction we are having would be worked with based on minutes. Let’s do this!
On Monday, she practiced 11/4 hours. This means she practiced 11/4 * 60 minutes = 165 minutes
On Tuesday, practice was for 19/8 hours. This means she had practiced for 19/8 *60 = 142.5 minutes
Lastly, on Wednesday, her practice time was 2.6 hours and that is 2.6 * 60 = 156 minutes
Kindly note that 2 hours is same as 120 minutes. We just need to know which of these minutes is closest to 120 minutes. From what we have, 142.5 is the closest.
This means that her practice on Wednesday is the closest to two hours.