To find the maximum and minimum values of the function
f(x) = 2x^3 - 4x + 3, we need to find the first
derivative.
f(x) = 2x^3 - 4x +
3
f’(x) = 6x^2 - 4
Equate this
to zero and solve for x
6x^2 - 4 =
0
=> x ^2 =
4/6
=> x = +sqrt (2/3) and x = -sqrt
(2/3)
To determine whether the values are minimum or
maximum, we find the second derivative
f’’(x) =
12x.
As f’’(x) is positive at x = +sqrt (2/3), we have a
minimum value here.
And as f’’(x) is negative at x = -sqrt
(2/3), we have a maximum value here.
For x = +sqrt (2/3),
f(x) = 2*(2/3)*sqrt (2/3) - 4*sqrt (2/3) + 3
For x = -sqrt
(2/3), f(x) = -2*2/3*sqrt (2/3) + 4*sqrt (2/3)
+3
The maximum value of the function is
(8/3)*sqrt(2/3)+ 3 at x =
-sqrt(2/3)
And the minimum
value of the function is -(8/3)*sqrt(2/3) + 3 at x =
+sqrt(2/3).
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