Let f(x)=4x−3 and let c be the number that satisfies the Mean Value Theorem for f on the interval 1≤x≤3.What is c ?Choose 1 answer:(A) 1.5(B) 1.75(C) 2(D) 2.25
Q. Let f(x)=4x−3 and let c be the number that satisfies the Mean Value Theorem for f on the interval 1≤x≤3.What is c ?Choose 1 answer:(A) 1.5(B) 1.75(C) 2(D) 2.25
Check Function Continuity: To apply the Mean Value Theorem (MVT), we need to ensure that the function f(x) is continuous on the closed interval [1,3] and differentiable on the open interval (1,3). The function f(x)=4x−3 is continuous and differentiable where 4x - 3 > 0, which is when x > \frac{3}{4}. Since 1 > \frac{3}{4}, the function is continuous on [1,3] and differentiable on (1,3).
Mean Value Theorem Statement: The Mean Value Theorem states that there exists at least one number c in the open interval (1,3) such that f′(c)=b−af(b)−f(a), where a=1 and b=3.
Calculate f(a) and f(b): First, we calculate f(a) and f(b): f(a)=f(1)=4⋅1−3=1=1 f(b)=f(3)=4⋅3−3=9=3
Calculate Difference Quotient: Now, we calculate the difference quotient [f(b)−f(a)]/(b−a):3−1f(3)−f(1)=3−13−1=22=1
Find Derivative of f(x): Next, we find the derivative of f(x), f′(x): f′(x)=dxd[4x−3] To differentiate 4x−3, we use the chain rule: f′(x)=24x−31⋅dxd[4x−3] f′(x)=24x−31⋅4 f′(x)=4x−32
Set f′(c) equal to Difference Quotient: Now, we set f′(c) equal to the difference quotient we found earlier, which is 1:4c−32=1To solve for c, we multiply both sides by 4c−3 and then divide by 2:2=4c−322=(4c−3)24=4c−34+3=4c7=4cc=47c=1.75