Let f be the function defined by f(x)=x3. If six subintervals of equal length are used, what is the value of the midpoint Riemann sum approximation for ∫03x3dx ? Round to the nearest thousandth if necessary.Answer:
Q. Let f be the function defined by f(x)=x3. If six subintervals of equal length are used, what is the value of the midpoint Riemann sum approximation for ∫03x3dx ? Round to the nearest thousandth if necessary.Answer:
Determine Width of Subintervals: Determine the width of each subinterval. Since we are integrating from 0 to 3 and using six subintervals, the width (Δx) of each subinterval is (3−0)/6=0.5.
Calculate Midpoints: Calculate the midpoints of each subinterval.The midpoints for the six subintervals are found by adding half of the width of a subinterval to the lower bound of each subinterval. The midpoints mi are: 0.25, 0.75, 1.25, 1.75, 2.25, and 2.75.
Evaluate Function at Midpoints: Evaluate the function f(x)=x3 at each midpoint.We calculate f(mi) for each midpoint:f(0.25)=0.253=0.015625f(0.75)=0.753=0.421875f(1.25)=1.253=1.953125f(1.75)=1.753=5.359375f(2.25)=2.253=11.390625f(2.75)=2.753=20.796875
Multiply by Subinterval Width: Multiply each function value by the width of the subinterval.We multiply each f(mi) by Δx to get the area of the rectangle for each subinterval:A1=f(0.25)×Δx=0.015625×0.5=0.0078125A2=f(0.75)×Δx=0.421875×0.5=0.2109375A3=f(1.25)×Δx=1.953125×0.5=0.9765625A4=f(1.75)×Δx=5.359375×0.5=2.6796875A5=f(2.25)×Δx=11.390625×0.5=5.6953125A6=f(2.75)×Δx=20.796875×0.5=10.3984375
Sum Rectangle Areas: Sum the areas of all rectangles to find the midpoint Riemann sum approximation.The midpoint Riemann sum approximation is the sum of all the areas:R=A1+A2+A3+A4+A5+A6R=0.0078125+0.2109375+0.9765625+2.6796875+5.6953125+10.3984375R=19.96875
Round Result: Round the result to the nearest thousandth if necessary.R=19.96875, which is already to the nearest thousandth.
More problems from Evaluate definite integrals using the power rule