Answer:
C ∫[-a,0] = -∫[0, a]
Explanation:
You want an alternate representation of the given integral ...
∫(2x⁵ -5x³)dx
on the interval [-a, a].
Odd function
The function f(x) = 2x⁵ -5x³ being integrated is an odd function. This means ...
f(-x) = -f(x) and f(0) = 0
Even function
An even function is characterized by ...
f(-x) = f(x)
The integral F(x) of this odd function f(x) is an even function, so the parts either side of x=0 have the integrals ...


As we can see, these integrals are the opposites of each other, matching answer choice C.
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Additional comment
The second attachment shows a numerical value for a=2.