Question

If PQ and PR are the two sides of a triangle, then the angle between them which gives maximum area of the triangle is ______.

Options

• π

• `pi/3`

• `pi/4`

• `pi/2`

Answer 1

If PQ and PR are the two sides of a triangle, then the angle between them which gives maximum area of the triangle is `underline(pi/2)`.

Explanation:

Let PQ = a and PR = b, then Δ = `1/2`ab sin θ

∵ - 1 ≤ sin θ ≤ 1

Since area is maximum when sin θ = 1

⇒ θ = `pi/2`