Answer:
dA(r) = 6.9 cm²
Step-by-step explanation:
Area of a rectangle is
A(r) = L * W (1)
Where L stands for length and W for width.
Taking differentials on both sides f equation (1)
dA(r) = W*dL + L*dW
As error in measurments are at most 0,1 cm ( in each side), then the maximum error in calculating the area is
dA(r) = 24* ( 0,1) (cm²) + 45*(0,1)(cm²) ⇒ dA(r) = 2.4 + 4.5 (cm²)
dA(r) = 6.9 cm²
