Answer:
D
Step-by-step explanation:
The average rate of change of f(x) in the closed interval [ a, b ] is
[tex]\frac{f(b)-f(a)}{b-a}[/tex]
Here { a, b ] = [ - 1, 2 ], thus
f(b) = 4 ← from (2, 4 )
f(a) = [tex]\frac{1}{2}[/tex] ← from (- 1, [tex]\frac{1}{2}[/tex] ) , thus
average rate of change = [tex]\frac{4-\frac{1}{2} }{2-(-1)}[/tex] = [tex]\frac{\frac{7}{2} }{3}[/tex] = [tex]\frac{7}{6}[/tex] → D
