Q.36 to 65 (Two marks Questions)Q.Consider the function f(x) = 2x3-3x2...
Global Minimum of f(x) = 2x^3 - 3x^2 in the domain [-1, 2]To find the global minimum of the given function f(x) = 2x^3 - 3x^2 in the domain [-1, 2], we need to analyze the critical points and endpoints of the function within the given domain.
- Finding the critical points:
To find the critical points, we need to find the values of x where the derivative of the function is equal to zero or undefined.
The derivative of f(x) is obtained by differentiating each term of the function with respect to x:
f'(x) = d/dx (2x^3) - d/dx (3x^2)
= 6x^2 - 6x
Next, we set f'(x) = 0 and solve for x:
6x^2 - 6x = 0
6x(x - 1) = 0
So, the critical points are x = 0 and x = 1.
- Finding the endpoints:
The given domain is [-1, 2], which means we need to evaluate the function at x = -1 and x = 2 as well.
f(-1) = 2(-1)^3 - 3(-1)^2
= -2 - 3
= -5
f(2) = 2(2)^3 - 3(2)^2
= 16 - 12
= 4
- Comparing the values:
Now, we compare the values of the critical points and endpoints to find the global minimum.
f(0) = 2(0)^3 - 3(0)^2
= 0
f(1) = 2(1)^3 - 3(1)^2
= 2 - 3
= -1
We can see that the minimum value of f(x) within the given domain is -5, which occurs at x = -1.
Therefore, the global minimum of f(x) = 2x^3 - 3x^2 in the domain [-1, 2] is -5.