Jawapan

2016-01-19T23:46:45+08:00
A = 9
d = 16 - 9
d = 7

Tn = 233
a + (n-1)d = 233
9 + (n - 1)7 = 233
7(n - 1) = 224
n - 1 = 32
n = 33

Sn 
= n/2 [2a + (n - 1)d]
= 33/2 [2(9) + 32(7)]
= 3993
1 5 1
2016-01-20T19:25:05+08:00
Tn = 233
a + (n-1)d = 233
9 + (n - 1)7 = 233
7(n - 1) = 224
n - 1 = 32
n = 33

Sn 
= n/2 [2a + (n - 1)d]
= 33/2 [2(9) + 32(7)]
= 3993