self Maths Puzzle

in a sequence A(n) is defined by,A(1)=2 and A(n+1)=A(n)+2*n. find the value of A(200).

Read Solution (Total 3)

A(1)=2; A(2)=4; A(3)=8; A(4)=14;A(5)=22; A(6)=32; A(7)=44 A(8)=58; it is clear that A(n)=A(1)+[(n)(n-1)]..........hence A(200)=A(1)+(200)(199)------>A(200)=2+39800=39802........So A(200)=39802
11 years agoHelpfull: Yes(4) No(0)

A(199+1) = (2 + 2*1 + 2*2 + 2*3 +........2*199)
= 2(1 + (1 +2 + 3 +....+199))
= 2(1 + (199*(199+1)/2))
= 2 +199*200
=39802
11 years agoHelpfull: Yes(2) No(0)
A(200)= 2+2(1+2+3+3+.......+199)=39802....
11 years agoHelpfull: Yes(0) No(0)

self Other Question

in how many ways can we distribute 10 identical looking pencils to 4 students so that each student gets at least 1 pencil? A man builds a four-walled house. Each of the walls, on the outside, face due south. The man looks out the window and sees a bear. What colour is the bear?