(One steel rod’s volume) = 3.14 x 4^2 x 20
= 1004.8cm^3
(Used steel) / (One steel rod’s volume) =
(Made steel rod’s number)
The answer is 28
Answer with explanation:
Let us assume that the 2 functions are:
1) f(x)
2) g(x)
Now by definition of concave function we have the first derivative of the function should be strictly decreasing thus for the above 2 function we conclude that
![\frac{d}{dx}\cdot f(x)](https://tex.z-dn.net/?f=%5Cfrac%7Bd%7D%7Bdx%7D%5Ccdot%20f%28x%29%3C0%5C%5C%5C%5C%5Cfrac%7Bd%7D%7Bdx%7D%5Ccdot%20g%28x%29%3C0)
Now the sum of the 2 functions is shown below
![y=f(x)+g(x)](https://tex.z-dn.net/?f=y%3Df%28x%29%2Bg%28x%29)
Diffrentiating both sides with respect to 'x' we get
![\frac{dy}{dx}=\frac{d}{dx}\cdot f(x)+\frac{d}{dx}\cdot g(x)\\\\](https://tex.z-dn.net/?f=%5Cfrac%7Bdy%7D%7Bdx%7D%3D%5Cfrac%7Bd%7D%7Bdx%7D%5Ccdot%20f%28x%29%2B%5Cfrac%7Bd%7D%7Bdx%7D%5Ccdot%20g%28x%29%5C%5C%5C%5C)
Since each term in the right of the above equation is negative thus we conclude that their sum is also negative thus
![\frac{dy}{dx}](https://tex.z-dn.net/?f=%5Cfrac%7Bdy%7D%7Bdx%7D%3C0)
Thus the sum of the 2 functions is also a concave function.
Part 2)
The product of the 2 functions is shown below
![h=f(x)\cdot g(x)](https://tex.z-dn.net/?f=h%3Df%28x%29%5Ccdot%20g%28x%29)
Diffrentiating both sides with respect to 'x' we get
![h'=\frac{d}{dx}\cdot (f(x)\cdot g(x))\\\\h'=g(x)f'(x)+f(x)g'(x)](https://tex.z-dn.net/?f=h%27%3D%5Cfrac%7Bd%7D%7Bdx%7D%5Ccdot%20%28f%28x%29%5Ccdot%20g%28x%29%29%5C%5C%5C%5Ch%27%3Dg%28x%29f%27%28x%29%2Bf%28x%29g%27%28x%29)
Now we can see the sign of the terms on the right hand side depend on the signs of the function's themselves hence we remain inconclusive about the sign of the product as a whole. Thus the product can be concave or convex.
Answer:
he can buy 10 peaches.
Step-by-step explanation:
7 mangoes will be 12.25. so you subtract his original money(20) from 12.25 which gives you 7.75. then divide 7.75 by 0.75(cost of a peach) and your answer will be 10(rounded off).
A and B are correct... reason is because hundredths is 1/10 to tenths and tenths are 10 times bigger than hundredths. C and D are wrong.
Hope this helped!
Nate