Let g(x)=x3+12x2+36x and let c be the number that satisfies the Mean Value Theorem for g on the interval −8≤x≤−2.What is c ?Choose 1 answer:(A) −7(B) −6(C) −3(D) −1
Q. Let g(x)=x3+12x2+36x and let c be the number that satisfies the Mean Value Theorem for g on the interval −8≤x≤−2.What is c ?Choose 1 answer:(A) −7(B) −6(C) −3(D) −1
Mean Value Theorem Explanation: The Mean Value Theorem states that if a function g is continuous on the closed interval [a,b] and differentiable on the open interval (a,b), then there exists at least one number c in the interval (a,b) such that g′(c) is equal to the average rate of change of the function over [a,b]. The average rate of change is given by (g(b)−g(a))/(b−a).
Calculate g(−2) and g(−8): First, we need to find g(−2) and g(−8) to calculate the average rate of change of g(x) on the interval [−8,−2]. g(−2)=(−2)3+12(−2)2+36(−2)=−8+48−72=−32 g(−8)=(−8)3+12(−8)2+36(−8)=−512+768−288=−32
Calculate Average Rate of Change: Now, we calculate the average rate of change of g(x) on the interval [−8,−2]. Average rate of change = (g(−2)−g(−8))/(−2−(−8))=(−32−(−32))/(6)=0/6=0
Find Derivative g′(x): Next, we need to find g′(x), the derivative of g(x), to find the value of c that satisfies g′(c)= average rate of change.g′(x)=dxd[x3+12x2+36x]=3x2+24x+36
Solve for c: We set g′(c) equal to the average rate of change and solve for c.0=g′(c)=3c2+24c+36This is a quadratic equation in the form of 3c2+24c+36=0.
Quadratic Equation Solution: We can solve the quadratic equation by factoring or using the quadratic formula. Since the equation is already factored as 3(c2+8c+12)=0, we can factor further to find the roots.3(c+6)(c+2)=0
Final Value of c: Setting each factor equal to zero gives us the potential values for c.c+6=0 or c+2=0c=−6 or c=−2
Final Value of c: Setting each factor equal to zero gives us the potential values for c. c+6=0 or c+2=0 c=−6 or c=−2However, c must be in the open interval (−8,−2), so c cannot be −2. Therefore, the only value that satisfies the Mean Value Theorem in the given interval is c=−6.