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Definite Integral of Derivative Function

∫−11g′(x) dx=\int_{-1}^1 g'(x) \, dx =

Options

A

2g(−1)2g(-1)

B

00

C

−2g(1)-2g(1)

D

2g(1)2g(1)

Correct

Step-by-Step Solution

To evaluate the definite integral ∫−11g′(x) dx\int_{-1}^1 g'(x) \, dx, we use the Fundamental Theorem of Calculus:

∫−11g′(x) dx=[g(x)]−11=g(1)−g(−1)\int_{-1}^1 g'(x) \, dx = \left[ g(x) \right]_{-1}^1 = g(1) - g(-1)

From the definition of the function g(x)g(x) (which is an odd function, satisfying g(−x)=−g(x)g(-x) = -g(x) for all xx in its domain):

g(−1)=−g(1)g(-1) = -g(1)

Substituting this relation into the evaluated integral:

∫−11g′(x) dx=g(1)−(−g(1))=g(1)+g(1)=2g(1)\int_{-1}^1 g'(x) \, dx = g(1) - (-g(1)) = g(1) + g(1) = 2g(1)

Thus, the correct option is (D).