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Definite integrals properties review

AP.CALC:
FUN‑6 (EU)
,
FUN‑6.A (LO)
,
FUN‑6.A.1 (EK)
,
FUN‑6.A.2 (EK)
Review the definite integral properties and use them to solve problems.

What are the definite integral properties?

Sum/Difference: integral, start subscript, a, end subscript, start superscript, b, end superscript, open bracket, f, left parenthesis, x, right parenthesis, plus minus, g, left parenthesis, x, right parenthesis, close bracket, d, x, equals, integral, start subscript, a, end subscript, start superscript, b, end superscript, f, left parenthesis, x, right parenthesis, d, x, plus minus, integral, start subscript, a, end subscript, start superscript, b, end superscript, g, left parenthesis, x, right parenthesis, d, x
Want to learn more about this property? Check out this video.
Constant multiple: integral, start subscript, a, end subscript, start superscript, b, end superscript, k, dot, f, left parenthesis, x, right parenthesis, d, x, equals, k, integral, start subscript, a, end subscript, start superscript, b, end superscript, f, left parenthesis, x, right parenthesis, d, x
Want to learn more about this property? Check out this video.
Reverse interval: integral, start subscript, a, end subscript, start superscript, b, end superscript, f, left parenthesis, x, right parenthesis, d, x, equals, minus, integral, start subscript, b, end subscript, start superscript, a, end superscript, f, left parenthesis, x, right parenthesis, d, x
Want to learn more about this property? Check out this video.
Zero-length interval: integral, start subscript, a, end subscript, start superscript, a, end superscript, f, left parenthesis, x, right parenthesis, d, x, equals, 0
Want to learn more about this property? Check out this video.
Adding intervals: integral, start subscript, a, end subscript, start superscript, b, end superscript, f, left parenthesis, x, right parenthesis, d, x, plus, integral, start subscript, b, end subscript, start superscript, c, end superscript, f, left parenthesis, x, right parenthesis, d, x, equals, integral, start subscript, a, end subscript, start superscript, c, end superscript, f, left parenthesis, x, right parenthesis, d, x
Want to learn more about this property? Check out this video.

Practice set 1: Using the properties graphically

Problem 1.1
integral, start subscript, minus, 2, end subscript, start superscript, 0, end superscript, f, left parenthesis, x, right parenthesis, d, x, plus, integral, start subscript, 0, end subscript, cubed, f, left parenthesis, x, right parenthesis, d, x, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
unitssquared

Want to try more problems like this? Check out this exercise.

Practice set 2: Using the properties algebraically

Problem 2.1
integral, start subscript, minus, 1, end subscript, cubed, f, left parenthesis, x, right parenthesis, d, x, equals, minus, 2
integral, start subscript, minus, 1, end subscript, cubed, g, left parenthesis, x, right parenthesis, d, x, equals, 5
integral, start subscript, minus, 1, end subscript, cubed, left parenthesis, 3, f, left parenthesis, x, right parenthesis, minus, 2, g, left parenthesis, x, right parenthesis, right parenthesis, d, x, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text

Want to try more problems like this? Check out this exercise.

Want to join the conversation?

  • blobby green style avatar for user gcoates0520
    How would I graph an equation like g(x)=3f(x-2)+1?
    (2 votes)
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  • blobby green style avatar for user 😊
    Proof of.
    |f(x)g(x)d(x)=|f(c)g(x)d(x)
    c€[a,b].

    |~integration from a-b
    (1 vote)
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    • cacteye blue style avatar for user Jerry Nilsson
      ∫(𝑎, 𝑏) 𝑓(𝑥)𝑑𝑥 and ∫(𝑎, 𝑏) 𝑓(𝑐)𝑑𝑥 are not equivalent expressions.

      Example:
      𝑎 = 0, 𝑏 = 2
      𝑓(𝑥) = 𝑥 ⇒ ∫(𝑎, 𝑏) 𝑓(𝑥)𝑑𝑥 = ∫(0, 2) 𝑥𝑑𝑥 = 2²∕2 − 0²∕2 = 2
      𝑐 = 2𝑥 ⇒ 𝑓(𝑐) = 2𝑥 ⇒ ∫(𝑎, 𝑏) 𝑓(𝑐)𝑑𝑥 = ∫(0, 2) 2𝑥𝑑𝑥 = 2 ∙ ∫(0, 2) 𝑥𝑑𝑥 = 2 ∙ 2 = 4
      (2 votes)
  • leafers tree style avatar for user lz40247
    If the f(x) inside is f(3x) instead of 3f(x), do you multiply the 3 to the bound values (a and b)? (does then become F(3b)- F(3a)?)
    (1 vote)
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  • blobby green style avatar for user ashwin123robotix
    how do u integrate xdx between bounds x and 0
    (1 vote)
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  • blobby green style avatar for user Z.Ashtab
    integral f(x) from 3a to 3b equal to integral 3f(3x)from a to b. is this right?
    (0 votes)
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    • piceratops ultimate style avatar for user Pat Florence
      No, this is not true. Integrating from 3a to 3b would mean you are changing the bounds of integration - it totally depends on what the function looks like over the interval from x=3a to x=3b. It may look the same as it does over the interval from x=a to x=b, but odds are it doesn't.
      (2 votes)
  • blobby green style avatar for user 8023834
    $\sqrt{x}$ does this work?///
    $$ \int_0^8 f(x) = \left[ x + \frac{1}{10} \cdot \frac{x^3}{3} \right]_0^8 = 12 + \frac{12^3}{30} - 0 = 12+56.6 = 69.6 $$
    (0 votes)
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