Math Problem Statement

Evaluate.

Integral from negative 3 to 5 left parenthesis 4 x squared minus 5 x plus 6 right parenthesis dx

Solution

To evaluate the definite integral

35(4x25x+6)dx,\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx,

we follow these steps:


Step 1: Find the indefinite integral

First, compute the indefinite integral of the function 4x25x+64x^2 - 5x + 6:

(4x25x+6)dx=4x335x22+6x+C\int \left(4x^2 - 5x + 6\right) dx = \frac{4x^3}{3} - \frac{5x^2}{2} + 6x + C


Step 2: Evaluate the definite integral

Now, evaluate the definite integral by substituting the bounds of integration:

35(4x25x+6)dx=[4x335x22+6x]35.\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx = \left[\frac{4x^3}{3} - \frac{5x^2}{2} + 6x\right]_{-3}^{5}.

Substitute x=5x = 5:

4(5)335(5)22+6(5)=4(125)35(25)2+30.\frac{4(5)^3}{3} - \frac{5(5)^2}{2} + 6(5) = \frac{4(125)}{3} - \frac{5(25)}{2} + 30.

Simplify each term:

4(125)3=5003,5(25)2=1252,6(5)=30.\frac{4(125)}{3} = \frac{500}{3}, \quad \frac{5(25)}{2} = \frac{125}{2}, \quad 6(5) = 30.

So, at x=5x = 5:

50031252+30.\frac{500}{3} - \frac{125}{2} + 30.

Next, substitute x=3x = -3:

4(3)335(3)22+6(3)=4(27)35(9)2+(18).\frac{4(-3)^3}{3} - \frac{5(-3)^2}{2} + 6(-3) = \frac{4(-27)}{3} - \frac{5(9)}{2} + (-18).

Simplify each term:

4(27)3=36,5(9)2=452,6(3)=18.\frac{4(-27)}{3} = -36, \quad \frac{5(9)}{2} = \frac{45}{2}, \quad 6(-3) = -18.

So, at x=3x = -3:

3645218.-36 - \frac{45}{2} - 18.


Step 3: Combine results

Now subtract the results at x=3x = -3 from the results at x=5x = 5:

  1. At x=5x = 5: 50031252+30\frac{500}{3} - \frac{125}{2} + 30
  2. At x=3x = -3: 3645218-36 - \frac{45}{2} - 18

Simplify:

35(4x25x+6)dx=(50031252+30)(3645218).\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx = \left(\frac{500}{3} - \frac{125}{2} + 30\right) - \left(-36 - \frac{45}{2} - 18\right).

Expand and combine:

=50031252+30+36+452+18.= \frac{500}{3} - \frac{125}{2} + 30 + 36 + \frac{45}{2} + 18.

Group fractions and constants:

=5003+(1252+452)+(30+36+18).= \frac{500}{3} + \left(-\frac{125}{2} + \frac{45}{2}\right) + \left(30 + 36 + 18\right).

Simplify each group:

  1. Constants: 30+36+18=8430 + 36 + 18 = 84,
  2. Fractions: 1252+452=802=40-\frac{125}{2} + \frac{45}{2} = -\frac{80}{2} = -40.

Combine everything:

35(4x25x+6)dx=500340+84.\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx = \frac{500}{3} - 40 + 84.

Simplify:

35(4x25x+6)dx=5003+44.\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx = \frac{500}{3} + 44.

Express as a single fraction:

35(4x25x+6)dx=5003+1323=6323.\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx = \frac{500}{3} + \frac{132}{3} = \frac{632}{3}.


Final Answer:

35(4x25x+6)dx=6323.\int_{-3}^{5} \left(4x^2 - 5x + 6\right) dx = \frac{632}{3}.


Would you like me to explain any step in more detail or provide further examples?

Related Questions:

  1. How do definite integrals represent the area under the curve?
  2. What is the role of the Fundamental Theorem of Calculus in evaluating integrals?
  3. How do you handle improper integrals where the bounds are infinite?
  4. Can you explain the geometric interpretation of negative results in definite integrals?
  5. How can definite integrals be used in physics or engineering applications?

Tip:

Always simplify terms systematically when evaluating definite integrals to avoid errors in arithmetic!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Definite Integrals
Polynomial Integration
Fundamental Theorem of Calculus

Formulas

Indefinite integral: ∫(ax^n)dx = (ax^(n+1))/(n+1) + C for n ≠ -1
Definite integral: ∫[a,b] f(x)dx = F(b) - F(a)

Theorems

Fundamental Theorem of Calculus

Suitable Grade Level

Grades 11-12