Answer:
A) 0
Step-by-step explanation:
Use second fundamental theorem of calculus.
f(x) = ∫₄²ˣ √(x² − t) dt
f'(x) = √(x² − 2x) (2)
f'(x) = 2√(x² − 2x)
f'(2) = 2√((2)² − 2(2))
f'(2) = 0