The sequence is defined by A(1)=2 and A(n+1)=A(n)+2n.
What is the value of A(100)
(1)9902
(2)9900
(3)10100
(4)9904

• A(100)=A(99)+2*99
  same here
  A(100)=A(1)+2*(1+2+3+.....+99)
  A(100)=2+9900
  A(100)=9902
  ans is (1)9902
• 12 years agoHelpfull: Yes(24) No(2)
• A(1)=2
  A(2)=A(1)+2(2)
  A(3)=A(2)+2(3)=A(1)+2(2)+2(3)
  A(4)=A(3)+2(4)=A(1)+2(2)+2(3)+2(4)
  ......
  ......
  A(100)=A(1)+2(2)+2(3)+2(4)+.....+2(100)
  =2+2(2)+2(3)+......+2(100) ________________A(1)=2
  =2[1+2+3+.......100]
  =2*[100*101/2] _______________sum of 1,2,3....n=n(n+1)/2
  =100*101
  .'. ans =10100
• 12 years agoHelpfull: Yes(0) No(2)