The graph of the function
is
- concave upward, when

- concave downward, when

Find 
1.

2.

Now:
1. when
the graph of the function is concave upward and this is for

2. when
the graph of the function is concave downward and this is for

Answer:
Step-by-step explanation:
The sum of the ages of a Mother and her son is 78 , three years ago the mother is five times as old as the son, what is their present ages?
To solve this , let the age of the mother be x and the age of the son be y , from the first statement :
x + y = 78
Three years ago , the mother will be x- 3 and the son will be y - 3 , from the second statement:
x - 3 = 5 ( y-3)
x- 3 = 5y - 15
x - 5y = -12
The resulting equations are
x + y = 78
x - 5y = -12
This is called a simultaneous linear equation , that means it is a linear equation.
The side of a square is xcm , if the difference between the area and the perimeter is 12 , find the legth of its side.
Interpretation:
The formula for the area of a square is
and the perimeter is 4l , from the question , we have
- 4x = 12
This is not a linear equation , it is simply a quadratic equation , so the situation is non linear
In calculus, the squeeze theorem, also known as the pinching theorem, the sandwich theorem, the sandwich rule, the police theorem, the between theorem and sometimes the squeeze lemma, is a theorem regarding the limit of a function. In Italy, the theorem is also known as theorem of carabinieri.
Answer:
Step-by-step explanation:
3.2 times 1.5 plus 6 times4.2= 30 meters of carpet.