The graph of the polynomial p(x) = 2x^2 + 4x + 3 has its least value at the point.
Answers
Step-by-step explanation:
f(x) = 2 x² + 4x +3
f'(x)= 4x+4
f"(x)=4
To find critical number, f'(x)=0
4x+4=0
x= -1
66
when x=-1, f"(x) is positive
By second derivative test, f atttains minimum at x= -1.
The minimum value=f(-1)
=2-4+3=1
The minimum point is (-1,1)
Given : -
- Polynomial function is p(x) = 2x² + 4x + 3
To find : -
- The coordinates where the given polynomial has its least value.
Solution : -
We are aware about the general form of a quadratic polynomial :
- ax² + bx + c
By comparing it with the given polynomial, we get :
- a = 2
- b = 4
- c = 3
To find the least value of x, we use the formula :
- Min ( x ) = -b/2a
So,
⇒ Min ( x ) = -4/(2×2)
⇒ Min ( x ) = - 4/4
⇒ Min ( x ) = -1
So the value of x where the polynomial has it's least value is -1.
Now substitute value of x in given polynomial to find y
⇒ p(x) = 2x² + 4x + 3
⇒ p(-1) = 2 (-1)² + 4(-1) + 3
⇒ y = 2 ( 1 ) - 4 + 3
⇒ y = 2 - 4 + 3
⇒ y = 1
From our above results, we obtained that, the minimum value of the given polynomial function is on (-1,1)
Refer to the graph in attachment for verification.