Question

Resolva os logaritimos

a) log x 1/7 = -1
b) log x 8 = -3
c) log 81 = 4/3​

Answer 1

Boa noite

a)logx (1/7)=-1

1/7=x^-1

1/7=1/x

x=7.

b)logx (8)= -3

8=x^-3

8=1/x^3

8x^3=1

x^3=1/8

x^3=1/2^3

x=raiz cubica√(1/2^3)

x=1/2.

c)log 81=4/3 (incógnita??)