(a)
False. For example if
f(x)={01for x<0for x≥0
then ∫−3−2f(x)dx=0 and −∫32f(x)dx=∫23f(x)dx=1.

(b)
False. For example, if f(x)=x, then ∫−3−2f(x)dx is negative while
∫23f(x)dx is positive, so they cannot be the same.

(c)
False. For example, consider the functions
f(x)={01for x<21for x≥21andg(x)={01for x≥21for x<21
Then f(x)⋅g(x)=0 for all x, so ∫01f(x)⋅g(x)dx=0. However,
∫01f(x)dx=21 and ∫01g(x)dx=21, so ∫01f(x)dx⋅∫01g(x)dx=41.

