Answer: 4 cakes left in all.
Step-by-step explanation:
Given: Cakes left on first day= 
Cakes left on second day =
The number of cakes left in all=
⇒The number of cakes left in all=
Therefore, The number of cakes left in all=4
In case you're not already aware, the expression 
is called the "difference quotient" and represents the average rate of change of a function 
over an interval ![[x,x+h]](https://tex.z-dn.net/?f=%5Bx%2Cx%2Bh%5D)
.
For the function 
, by substituting 
we get
Then the difference quotient is
where the last equality holds as long as 
.
To answer this question you have to create a system of equations. The first equation will be that Devi's money (x) equals her brother's money (y), or x = y. The next equation would be that (3/5)x + (7/10)y = 78. You than can substitute x in for y because x = y. The equation would know be (3/5)x + (7/10)x = 78. You then combine the like terms to create an equation of (13/10)x = 78. Then, multiply both sides by 10 / 13 in order to isolate x. This will create the equation x = 60. This means that Devi and her brother each had 60 dollars. You then find out how much they spent and add it together. You can do so with the equation (2/5)x + (3/10)y = z, with z being total money spent. You substitute 60 in for x and for y then solve. When you solve you see that 24 + 18 = z, or that z equals 42. In other words, they spent 42 dollars altogether.
Answer:
dy/dx=sec^2^(x)-(-csc^2(x)
=sec^2(x)+ csc^2(x)
so solution is E
