Q. Let f(x)=−4x3+6x2−5.The absolute minimum value of f over the closed interval −2≤x≤3 occurs at what x value?Choose 1 answer:(A) −2(B) 3(C) 0(D) 1
Find Critical Points: To find the absolute minimum value of the function on the closed interval [−2,3], we first need to find the critical points of the function within the interval. Critical points occur where the derivative of the function is zero or undefined.
Calculate Derivative: We calculate the derivative of f(x)=−4x3+6x2−5.f′(x)=dxd(−4x3+6x2−5)=−12x2+12x.
Find Critical Points: Next, we find the critical points by setting the derivative equal to zero and solving for x.−12x2+12x=0x(−12x+12)=0x=0 or x=1.
Evaluate Function: We now have two critical points, x=0 and x=1, within the interval [−2,3]. We also need to evaluate the function at the endpoints of the interval, which are x=−2 and x=3.
Compare Values: We evaluate the function at the critical points and the endpoints:f(−2)=−4(−2)3+6(−2)2−5=−4(−8)+6(4)−5=32+24−5=51.f(0)=−4(0)3+6(0)2−5=−5.f(1)=−4(1)3+6(1)2−5=−4+6−5=−3.f(3)=−4(3)3+6(3)2−5=−4(27)+6(9)−5=−108+54−5=−59.
Absolute Minimum Value: Comparing the values of f(x) at the critical points and endpoints, we find that the absolute minimum value occurs at x=1, since f(1)=−3 is the smallest value.
Absolute Minimum Value: Comparing the values of f(x) at the critical points and endpoints, we find that the absolute minimum value occurs at x=1, since f(1)=−3 is the smallest value.The answer to the question prompt is that the absolute minimum value of the function f(x)=−4x3+6x2−5 over the interval [−2,3] occurs at x=1.