171. The argument of (1 – i) / (1 + i) is
172. How many terms of A.P. 21, 18, 15, 12, … must be taken to give the sum zero.
173. ( - 3 / 2) + (5 / 4) – (- 7 / 4)
174. The two geometric means between the numbers 1 and 64 are
175. The union of infinite number of open sets is
176. The number of triangles that can be formed with 10 points as vertices, n of them being collinear, is 110. Then n is
177. In how many ways 4 men and 4 women can be seated in a row so that men and women are alternate?
178. The number of diagonals that can be drawn by joining the vertices of an octagon is
179. Find the 5th term in the expansion ( 1 -2x )-1
16x4
180. If in expansion of (1 +y)n the coefficient of the 5th, 6th and the 7th terms are in A.P the n is equal to