" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
Un= 297
*cari n
Un= a+(n-1)b
297= 102+(n-1)3
297= 102+ 3n - 3
297= 99 + 3n
297- 99 = 3n
198 = 3n
198/3 = n
66 = n
*Sn = n/2( a + Un)
= 66/2( 102+297)
= 33 x 399
= 13167