211. Find the term independent of x in the expansion of (x2 + 1/x)9
212. The probability that a man will live 10 years is ¼ and the probability that his wife will live 10 more years is 1/3. Then the probability that neither will be alive in 10 years as
213. Solve a + b + c +d =1
-a + b -d = 1
a -b +c = 1
b +c = 1
214. Solve x -3y +6z = -1
2x -5y +10z = 0
3x -8y +17z = 1
215. Exogenous variables of a matrix are called
216. The number of all possible matrices of order 3x3 with each entry 0 or 1 is:
217. If A is a square matrix such that A2 = A, then (I + A )3 -7A is equal to
218. Matrices A and B will be inverse of each other only if
219. Find values of k if area of triangle is 4sq. units and vertices are (k, 0), (4,0), (0,2)
220. Equation of line joining (3,1), and(9,3) using determinants are