HOW MANY WAYS CAN 12 PERSONS TAKE SEATS IN ROW OF 20 SEATS,SO THAT EACH PERSON HAS EXACTLY ONE NEIGHBOUR???????????

HOW MANY WAYS CAN 12 PERSONS TAKE SEATS IN ROW OF 20 SEATS,SO THAT EACH PERSON HAS EXACTLY ONE NEIGHBOUR???????????

how to prepare for  iit jee 2009, in last 4 months????

scheduleor time table???

can any one say??

number of ways of dividing 13 men,13 women in to 13 couple each consist of a man and a women is?????

the total number of 5 digit number of different digits in which the digit in the middle is the largest is???

area bounded by the curves  0<y<x²+1; 

                                                    0<y<x+1;

                                                     0<x<2  is

 

x(1-x²)/(1+x⁴)  dx

[ 1+x/x^1/2]^1/2    dx

(x³+x²+x-1)/(x²-1)[(2-x²)^1/2]   dx

(2 sinx+sin 2x)/(cos x-1)[(cos x+cos²x+cos³x)^1/2]

(cos⁴x+sin⁴x+cos²x.sin²x)^-1