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

Now the sum of the 2 functions is shown below

Diffrentiating both sides with respect to 'x' we get

Since each term in the right of the above equation is negative thus we conclude that their sum is also negative thus

Thus the sum of the 2 functions is also a concave function.
Part 2)
The product of the 2 functions is shown below

Diffrentiating both sides with respect to 'x' we get

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.
The equation of the vertical parabola in vertex form is written as

Where (h, k) are the coordinates of the vertex and p is the focal distance.
The directrix of a parabola is a line which every point of the parabola is equally distant to this line and the focus of the parabola. The vertex is located between the focus and the directrix, therefore, the distance between the y-coordinate of the vertex and the directrix represents the focal distance.

Using this value for p and (3, 1) as the vertex, we have our equation
Answer:
Hello, Your answer would be 35 (Fraction 1 over 35)
Hope's this helped.
Step-by-step explanation: