Answer:
[0,3]
Step-by-step explanation:
Using a special case of mean value theorem, The Intermediate Zero Theorem:
if sign changes in continuous function, it pass through zero:
f(-5)=2, f(0)=-3. f(3)=2, f(7)=-4, f(8)=-1
[-5,0], [0,3], [3,7] guarantee a solution
smallest : [0,3]