Q. Let h(x)=x3+6x2+2.What is the absolute minimum value of h over the closed interval −6≤x≤2 ?Choose 1 answer:(A) 34(B) 2(C) −34(D) −2
Find Critical Points: To find the absolute minimum value of the function h(x) on the closed interval [−6,2], we first need to find the critical points of h(x) within the interval. Critical points occur where the derivative h′(x) is zero or undefined.
Calculate Derivative: Calculate the derivative of h(x) to find h′(x):h′(x)=dxd(x3+6x2+2)=3x2+12x
Set Equal to Zero: Set the derivative equal to zero to find the critical points:3x2+12x=0x(3x+12)=0This gives us two solutions: x=0 and x=−4.
Check Interval: Check if the critical points are within the closed interval [−6,2]. Both x=0 and x=−4 are within the interval, so we will evaluate h(x) at these points as well as at the endpoints of the interval, x=−6 and x=2.
Evaluate at −6: Evaluate h(x) at x=−6:h(−6)=(−6)3+6(−6)2+2=−216+216+2=2
Evaluate at −4: Evaluate h(x) at x=−4:h(−4)=(−4)3+6(−4)2+2=−64+96+2=34
Evaluate at 0: Evaluate h(x) at x=0:h(0)=(0)3+6(0)2+2=0+0+2=2
Evaluate at 2: Evaluate h(x) at x=2:h(2)=(2)3+6(2)2+2=8+24+2=34
Compare Values: Compare the values of h(x) at the critical points and the endpoints to determine the absolute minimum value: h(−6)=2h(−4)=34h(0)=2h(2)=34 The absolute minimum value of h(x) on the interval [−6,2] is 2, which occurs at both x=−6 and x=0.