Đáp án:
a)
`2^(x + 7) = 2^2 . 16 + 192`
`⇔ 2^(x + 7) = 4 . 16 + 192`
`⇔ 2^(x + 7) = 256`
`⇔ 2^(x + 7) = 2^8`
`⇒ x + 7 = 8`
`⇔ x = 1`
`S = {1}`
`---------`
b)
`7 + 2 . (x - 3) = 11`
`⇔ 7 + 2x - 6 = 11`
`⇔ 2x = 11 + 6 - 7`
`⇔ 2x = 10`
`⇔ x = 5`
`S = {5}`
`---------`
c)
`102 : [(2^x + 13) - 4] = 6`
`⇔ [(2^x + 13) - 4] = 102 : 6`
`⇔ [(2^x + 13) - 4] = 17`
`⇔ 2^x + 13 = 17 + 4`
`⇔ 2^x = 17 + 4 - 13`
`⇔ 2^x = 8`
`⇔ 2^x = 2^3`
`⇒ x = 3`
`S = {3}`