Jawabanmu

2014-02-25T20:40:44+07:00
A. n/2(a+a+29.b)= 15(1+1+116) =1770
b. n/2(a+a+29.b) = 15(8+8+232) = 3720
1 5 1
2014-02-25T21:06:02+07:00
B. S30 = 30/2 (2.1+(30-1)2
 = 15 (3+29.2)
= 15 (3) +58
= 15 . 61
= 915
, salah nih yang bener
S30 = 30/2 (2.8 + (30-1 ) 8
= 15 ( 16 + 29 . 8 ) = 15 (16 +232 ) = 15 . 248 = 3720 INI YANG B
NIH YANG A 30/2 (2.1 + 30-1 ) 4 = 15 (2 + 29 . 4 ) = 15 (2) + 116 = 15 . 118 = 1770