Answer:
A)

B)

Step-by-step explanation:
<em>x</em> and <em>y</em> are differentiable functions of <em>t, </em>and we are given the equation:

First, let's differentiate both sides of the equation with respect to <em>t</em>. So:
![\displaystyle \frac{d}{dt}\left[xy\right]=\frac{d}{dt}[6]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7Bd%7D%7Bdt%7D%5Cleft%5Bxy%5Cright%5D%3D%5Cfrac%7Bd%7D%7Bdt%7D%5B6%5D)
By the Product Rule and rewriting:
![\displaystyle \frac{d}{dt}[x(t)]y+x\frac{d}{dt}[y(t)]=0](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7Bd%7D%7Bdt%7D%5Bx%28t%29%5Dy%2Bx%5Cfrac%7Bd%7D%7Bdt%7D%5By%28t%29%5D%3D0)
Therefore:

A)
We want to find dy/dt when <em>x</em> = 4 and dx/dt = 11.
Using our original equation, find <em>y</em> when <em>x</em> = 4:

Therefore:

Solve for dy/dt:

B)
We want to find dx/dt when <em>x</em> = 1 and dy/dt = -9.
Again, using our original equation, find <em>y</em> when <em>x</em> = 1:

Therefore:

Solve for dx/dt:

Answer:

Step-by-step explanation:
The required answer is the rate at which Machine A works when the two machines are combined.
Note: the rate of doing work is express as

Hence we can conclude that Machine A working rate is
and machine B working rate is

When the two machine works together, the effective working rate is

The fraction of the work that Machine B will not have complete because of Machine A help is the total work done by machine A
Hence the fraction of work done by A is expressed as


Hence the fraction of the work that Machine B will not have complete because of Machine A help is the total work done by machine A is 
Answer:
Option (A)
Step-by-step explanation:
By satisfying the equation of a function 'f' by each coordinates given in the options we can get the point which lies on the graph of f(x) = 
Option (A). (1, 10)
f(1) = 
10 = 10
True.
Therefore, point (1, 10) lies on the graph.
Option (B). (0, 10)
f(0) = 
10 = 2
Not true.
Therefore, point (0, 10) doesn't lie on the graph.
Option (C). (10, 1)
f(10) = 
1 = 19531250
Not true.
Therefore, point (10, 1) doesn't lie on the graph.
Option (D). (0, 0)
f(0) = 
0 = 2
Not True.
Point (0, 0) doesn't lie on the graph.
Option (A) will be the answer.
Answer:

<h3><u>x=1 and x=</u><u>-</u><u>15</u> is the right answer.</h3>
Answer:
Option B is correct
Step-by-step explanation:
A function has form of f(x) = 2x + 3, or y = 2x + 3
To find the inverse of f(x), we are going to represent x in form of y.
To do this, we try to send all components containing x to one side of expression and send the other components to the other side of expression.
Now, let's do it.
y = 2x + 3
We firstly send 3 to the right, change the sign of 3 from + to -, we have:
y - 3 = 2x
We then rearrange both sides to get a standard form:
2x = y - 3
We now divide both sides by 2 to get the expression of x:
(2/2)x = (y - 3)/2
We simplify both sides of expression to obtain final result:
x = (1/2)y - 3/2
=> Inverse of f(x) is x = (1/2)y - 3/2
=> Option B is correct