Question

Resolva essa inequação exponencial
a) 3-4ˣ ≤ 72-6.4ˣ

b) 4ˣ⁺¹ . 2ˣ⁻¹ < 128

c) 25 ≥ 5/5ˣ

d) 3ˣ⁽ˣ⁺¹⁾ > 3ˣ²⁺¹

Answer 1

a)3-4ˣ ≤ 72-6.4ˣ

3-4ˣ ≤ 72-6×4ˣ
-4ˣ +6×4ˣ ≤ 72-3
5×4ˣ ≤ 69
4ˣ ≤ 69/5
x ≤ 1/2x long2 69/5




b)4ˣ +1×2ˣ-1 <128
(2²)ˣ⁺¹×2ˣ⁻¹<2^7
2^3×+1 <7
3×<7-1
3×<6
x <2



c)25≥ 5÷5ˣ,xer
25 ≥5^-x+1
5-×+1≤25
5^-×1≤ 5^2
-x≤1
x≥ -1