JAMB - Mathematics (2015 - No. 37)
Determine the third term of a geometrical progression whose first and second term are 2 and 54 respectively
1458
1485
1345
1258
Explicaţie
1st G.P. = a =2
2nd G.P. = ar\(^{2 −1}\) = 54
2(r) = 54
r = 54/2 = 27
r = 27
3rd term = ar\(^2\) = (2) (27)\(^2\)
2 × 27 × 27
= 1458
2nd G.P. = ar\(^{2 −1}\) = 54
2(r) = 54
r = 54/2 = 27
r = 27
3rd term = ar\(^2\) = (2) (27)\(^2\)
2 × 27 × 27
= 1458