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Ch. 5 - Integrals
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Not the one you use?Change textbook
Chapter 5, Problem 5.PE.9d

If ∫²₋₂ 3ƒ(x) dx = 12, ∫⁵₋₂ ƒ(x) dx = 6, and ∫⁵₋₂ g(x) dx = 2, find the value of each of the following.


d. ∫⁵₋₂ (-πg(x)) dx

Verified step by step guidance
1
Recall the property of definite integrals that allows constants to be factored out: for any constant \(c\), \(\int_a^b c \cdot h(x) \, dx = c \int_a^b h(x) \, dx\).
Apply this property to the integral \(\int_{-2}^5 (-\pi g(x)) \, dx\), rewriting it as \(-\pi \int_{-2}^5 g(x) \, dx\).
Use the given value \(\int_{-2}^5 g(x) \, dx = 2\) and substitute it into the expression to get \(-\pi \times 2\).
Express the integral in terms of \(\pi\) and the known value without calculating the numerical product, as per instructions.
Thus, the value of \(\int_{-2}^5 (-\pi g(x)) \, dx\) is \(-2\pi\) times the integral of \(g(x)\) over \([-2,5]\), which is \(-2\pi\).

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Properties of Definite Integrals

Definite integrals have linearity properties, meaning the integral of a sum is the sum of the integrals, and constants can be factored out. For example, ∫[a to b] c·f(x) dx = c·∫[a to b] f(x) dx. This allows simplification of integrals involving constants or sums of functions.
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