Question

URGENTE Resolva as inequacões exponenciais: a) 9^x > 3 b)(1/10)^x ≤ 1 c) 7^x > 1 d) (1/7)^X > 1 e) 1/3^x > 27 f) 1/5^x > ∛25

Answer 1

Resposta:

a) (1/3)^3x-1 = (1/3)^x+5

(1/3)³ˣ⁻¹ = (1/3)ˣ⁺⁵ ( BASES iguais (1/3))

3x - 1 = x + 5

3x - 1 - x = 5

3x - x = 5 + 1

2x = 6

x = 6/2

x = 3 ( resposta)

b)3^x = 243

3ˣ = 243 (243 = 3x3x3x3x3 = 3⁵)

3ˣ = 3⁵ ( bases iguais (3))

x = 5 ( resposta)

c) 0,7^3x = 7/10^x-4

0,7³ˣ = 7/10ˣ⁻⁴ (7/10 = 0,7)

0,7³ˣ = 0,7ˣ⁻⁴ ( base iguais (0,7))

3x = x - 4

3x - x = - 4

2x = - 4

x = - 4/2

x = - 2 ( resposta)