Question

Witam
mam 5 kótki zad. z logarytmu. :)

Answer 1

1.

logx (2x + 3) = 0      D:   x ≠ 1 i x > 0   i   2x + 3 > 0  

                                                                     x > -3/2

                                   D:   x ∈  (0, 1) u (1, +oo)

x^0 = 2x + 3

1 = 2x  +3

-2x = 3 - 1

-2x = 2

x = -1  ∉ D

równanie nie posiada rozwiazania

 

2.

log2 log3 81 = log2 log3 3^4 = log2 4 = log2 2^2 = 2

 

3.

10^(log 5) = 10^(log10 5) = 5

 

4.

M = log (x - 4)

D:  x - 4 > 0

      x > 4

odp. x ∈ (4, +oo)

 

4.

M = logx 7

D:  x ≠ 1 i x > 0

odp. x ∈ (0, 1) u (1, +oo)