jika 9 pangkat m +1 =82-9 pangkat m -1, nilai dari ekspresi 5 pangkat m +1 =

9^(m + 1) = 82 - 9^(m - 1)
9^(m + 1) + 9^(m - 1) = 82
9 . 9^m + 1/9 . 9^m = 82
(9 + 1/9) . 9^m = 82
(81 + 1)/9 . 9^m = 82
82/9 . 9^m = 82
1/9 . 9^m = 1
9^m = 9
m = 1

5^(m + 1) = 5^2 = 25