Polynomials related Questions by Balaji

[Balaji]

what is the sum of 1^2+3^2+5^2+....31^2 ?



a) 9455



b) 5456



c) 3468



d) 4892

answer choice b



solution



1^2+2^2+3^2......n^2 = (n(n+1)(2n+1))/6 



expression = ((31*32*63)/6)-((60*16*31)/6)



=5456


 

[Balaji]

Given that the month of may of a non leap year has 5 sundays what is the probability that the year started on a wednesday



a) 1/7



b) 1/3



c) 0



d) 1

answer choice  c



solution



probability of getting jan 1st being wednesday = 0




 

[Balaji]

N has p factors



2N has 2p factors



3N has 4P/3 factors 



which of the follow could be N?



a) 36



b) 38



c) 40



d) 45

answer choice d



solution



no of factor of N = (a+1)(b+1)(c+1)


no of factor of 3N = (a+2)(b+1)(c+1)







(a+2)/(a+1)


=4/3





a=2











N is odd  no that multiple of 9