Let k elementof Z Show that gcd 4k 2 k2 k 2Solution4k2 k
     Let k elementof Z. Show that gcd (4k + 2, k^2 + k) = 2. 
  
  Solution
4k+2 | k2 + k | k/4
k2 + k/2
.................................
0 + k/2 | 4k+2 | 8
4k
......................................
2 | k/2 | k/4
k/2
.......................................................
0
therefore , 2 is GCD

