Given that in ΔABC, ∠A = 40° and ∠B = 60°

We have to find longest and shortest side

We know that,

Now,

⇒ 40°<60°<80° ⇒ ∠A < ∠B < ∠C

⇒ ∠C is greater angle and ∠A is smaller angle

Now,

∠A < ∠B < ∠C

BC < AC < AB

[∵ Side opposite to greater angle is larger and side opposite to smaller angle is smaller]

∴ AB is longest and BC is smallest or shortest side.