The value of (2 /7) + (4 /7) + (6 /7) is equal to :

JEE Main 2022 Mathematics question

The value of is equal to :

Answer: (2)

Using cos A + cos(A + d) + … (n terms) = sin(nd/2)cos(A + (n − 1)d/2)/sin(d/2) with and n = 3: the sum is .

Create a free account to read the complete working, and practise questions like this in a timed test.

Question ID VK-034613