" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
U3 = 13 _
4 b = 16
b = 16:4 = 4
a = 5
Sn = n/2. (2a+(n-1)b)
S25 = 25/2 (2.5+( 25 -1 ) 4)
= 12,5 . (10+24.4)
= 12,5 . (10+ 96)
= 12,5. 106
= 1325