Find r if : P(11,r) = P(12,r-1)

Find r if : ^5P_r= "^6P_(r-1) .

Find r if "^5P_r =2 "^6P_(r-1) .

Find r if "^5P_r = "^6P_(r-1) .

Find r if : "^10P_r= 2^9P_r .

Find r if : ^10P_(r+1): "^11 P_(r)= 30:11 .

Find the value of r if 5. ^4P_r= 6. "^5P_(r-1) .

Find the value of r, if (i) .^(11)P_(r)=990 (ii) .^(8)P_(5)+5*^(8)P_(4)=^(9)P_(r)

Let A={p , q , r , s}\ a n d\ B={1,2,3}dot Which of the following relations from A to B is not function? (i) R_(1) = {(p, 1), (q, 2), (r, 1), (s, 2)} (ii) R_(2) = {(p, 1), (q, 2), (r, 1), (s, 1)} (iii) R_(3) = {(p, 1), (q, 2), (r, 2), (r, 2)} (iv) R_(4) = {(p, 2), (q, 3), (r, 2), (s, 2)}

Let A = (1,2,3) and R = (1,1), (2,2), (1,2), (2,1), (1,3) then R is