Question 3
A plane is divided into a number of non-overlapping polygons by using $n$ straight lines. Find the largest number of triangles that can be formed
(a) when $n=5$. (1 mark)
(b) when $n=6$. (2 marks)
(c) when $n=7$. (3 marks)
(a) when $n=5$. (1 mark)
(b) when $n=6$. (2 marks)
(c) when $n=7$. (3 marks)