Question

Determine o valor de x para: $4^{x} - 10. 2^{x} + 16 = 0$
Determine o valor de x para:$9^{x} - 4. 3^{x} + 3 = 0$

Answer 1

* 4ⁿ - 10.2ⁿ + 16 = (2ⁿ)²-10.2ⁿ + 16 = 0 ---› (2ⁿ-8).(2ⁿ-2) = 0 —› 2ⁿ = 8 —› n=3 ou 2ⁿ = 2 —› n = 1 ----- 9ⁿ - 4.3ⁿ + 3 = (3ⁿ)²- 4.3ⁿ +3 = 0 —› (3ⁿ-1).(3ⁿ-3) = 0 —› 3ⁿ = 1 —›n = 0 ou 3ⁿ = 3 —› n = 1