WAEC - Mathematics (2012 - No. 5)

The nth term of a sequence is Tn = 5 + (n - 1)2. Evaluate T4 - T6
30
16
-16
-30

Explanation

T4 = 5 + (4 - 1)2; where n = 4

= 5 + (3)2 = 5 + 9

= 14

T = 5 + (6 - 1)2

where n = 6

= 5 + (5)2

= 5 + 25 = 30

T4 + T6 = 14 - 30

= -16

Comments (0)

Advertisement