The area of the largest triangle that can be inscribed in a semi-circle of radius 4 cm in square centimetres is.

16 cm²

We know that,

Area of triangle = \(\frac{1}{2}\) × Base × Height

Radius of semi-circle = 4 cm

So,

The largest triangle that can be inscribed in a semi-circle will have a base equal to the diameter and a height equal to the radius of the semi-circle.

Base = 2 × R = 8 cm

Height = R = 4 cm

Area of the triangle = \(\frac{1}{2}\) × 8 × 4

= 4 × 4 = 16 cm²