Answer:
The bottom right (v shaped one) is a function
Step-by-step explanation:
Hope this helps:)
By definition, the number
is the ratio between the circumference and the diameter:

This implies that

And so your circumference is 
Answer:

Step-by-step explanation:
Given that

Here


We know that
M dx + N dy=0 will be exact if

So


it means that this is a exact equation.

Noe by integrating above equation

Given that
x= 0 then y= 1

C=4
So the our final equation will be

(2x^3+x+3)/(x+1)=2x^2-2x+3