Q. What is the area of the region between the graphs of f(x)=x2−4x+1 and g(x)=3x−5 from x=1 to x=4 ?Choose 1 answer:(A) 6125(B) 4(C) 227(D) 281
Set up integral: To find the area between two curves, we need to integrate the difference between the functions over the given interval. First, we need to set up the integral.
Calculate difference: The area A between the curves f(x) and g(x) from x=1 to x=4 is given by the integral of the absolute value of the difference between f(x) and g(x), which is A=∫14∣f(x)−g(x)∣dx.
Determine upper function: We calculate f(x)−g(x) for x in [1,4]. f(x)−g(x)=(x2−4x+1)−(3x−5)=x2−4x+1−3x+5=x2−7x+6.
Find intersection point: Since we are looking for the area between the curves, we need to find out which function is above the other in the interval from x=1 to x=4. We can do this by evaluating f(x) and g(x) at any point in the interval, for example at x=2.
Evaluate integral: Evaluating f(2) and g(2), we get f(2)=22−4⋅2+1=4−8+1=−3 and g(2)=3⋅2−5=6−5=1. Since g(2) > f(2), g(x) is above f(x) in at least some part of the interval. We need to check if this is true for the entire interval or if there is a point where f(x) and g(x) intersect.
Evaluate antiderivative: To find the intersection points, we set f(x) equal to g(x) and solve for x: x2−4x+1=3x−5. This simplifies to x2−7x+6=0.
Subtract antiderivatives: Factoring the quadratic equationx2−7x+6=0, we get (x−1)(x−6)=0. This gives us two solutions: x=1 and x=6. However, since we are only interested in the interval from x=1 to x=4, we only consider the intersection at x=1.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.We integrate g(x)−f(x)=(3x−5)−(x2−4x+1)=−x2+7x−6 from x=1 to x=4. The integral of g(x)2 is g(x)3, the integral of g(x)4 is g(x)5, and the integral of g(x)6 is g(x)7.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.We integrate g(x)−f(x)=(3x−5)−(x2−4x+1)=−x2+7x−6 from x=1 to x=4. The integral of g(x)2 is g(x)3, the integral of g(x)4 is g(x)5, and the integral of g(x)6 is g(x)7.We evaluate the antiderivative at the bounds x=4 and x=1 and subtract to find the area. The antiderivative evaluated at x=4 is f(x)1 and at x=1 is f(x)3.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.We integrate g(x)−f(x)=(3x−5)−(x2−4x+1)=−x2+7x−6 from x=1 to x=4. The integral of g(x)2 is g(x)3, the integral of g(x)4 is g(x)5, and the integral of g(x)6 is g(x)7.We evaluate the antiderivative at the bounds x=4 and x=1 and subtract to find the area. The antiderivative evaluated at x=4 is f(x)1 and at x=1 is f(x)3.Calculating the antiderivative at x=4 gives us f(x)5. Calculating the antiderivative at x=1 gives us f(x)7.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.We integrate g(x)−f(x)=(3x−5)−(x2−4x+1)=−x2+7x−6 from x=1 to x=4. The integral of g(x)2 is g(x)3, the integral of g(x)4 is g(x)5, and the integral of g(x)6 is g(x)7.We evaluate the antiderivative at the bounds x=4 and x=1 and subtract to find the area. The antiderivative evaluated at x=4 is f(x)1 and at x=1 is f(x)3.Calculating the antiderivative at x=4 gives us f(x)5. Calculating the antiderivative at x=1 gives us f(x)7.Now we subtract the antiderivative evaluated at x=1 from the antiderivative evaluated at x=4 to find the area: x=10.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.We integrate g(x)−f(x)=(3x−5)−(x2−4x+1)=−x2+7x−6 from x=1 to x=4. The integral of g(x)2 is g(x)3, the integral of g(x)4 is g(x)5, and the integral of g(x)6 is g(x)7.We evaluate the antiderivative at the bounds x=4 and x=1 and subtract to find the area. The antiderivative evaluated at x=4 is f(x)1 and at x=1 is f(x)3.Calculating the antiderivative at x=4 gives us f(x)5 = f(x)6 = f(x)7. Calculating the antiderivative at x=1 gives us f(x)9 = x=10 = x=11.Now we subtract the antiderivative evaluated at x=1 from the antiderivative evaluated at x=4 to find the area: x=14.Simplifying the expression, we get x=15.
Calculate final area: Since the intersection at x=1 is the start of our interval and there are no other intersections within the interval, we can conclude that g(x) is above f(x) for the entire interval from x=1 to x=4. Therefore, the area A is given by the integral from 1 to 4 of (g(x)−f(x))dx.We integrate g(x)−f(x)=(3x−5)−(x2−4x+1)=−x2+7x−6 from x=1 to x=4. The integral of g(x)2 is g(x)3, the integral of g(x)4 is g(x)5, and the integral of g(x)6 is g(x)7.We evaluate the antiderivative at the bounds x=4 and x=1 and subtract to find the area. The antiderivative evaluated at x=4 is f(x)1 and at x=1 is f(x)3.Calculating the antiderivative at x=4 gives us f(x)5. Calculating the antiderivative at x=1 gives us f(x)7.Now we subtract the antiderivative evaluated at x=1 from the antiderivative evaluated at x=4 to find the area: x=10.Simplifying the expression, we get x=11.The area of the region between the graphs of f(x) and g(x) from x=1 to x=4 is x=16 square units. This corresponds to answer choice (C) x=17, since x=18.