Question

Repede va rog , dau coroana​

Answer 1

Răspuns:

Explicație pas cu pas:

1.

3x+1=4

3x=3

x=1

2.

a.

$3^{x^{2} }=81\\ 3^{x^{2} }=3^{4}\\x^{2} =4,$

$x_{1,2}$ =±2

b.

$3^{x}(1+3+\frac{1}{9})=37\\3^{x}*\frac{37}{9}=37\\3^{x}=9, x=2$

c. $3^{x}=t; 9^{x}=t^{2}, t>0$

$t^{2}-12t+27=0$, $t_{1}=9, t_{2}=3$

$3^{x}=9, x_{1}=2$

$3^{x}=3, x_{3} =1$

d. $6^{2-x}=6^{3}$

2-x=3, x= -1

3. le faci singur

a. $3^{4}=x-1$, x=82

b. $3^{3}=(x-2)(x+4)$

c. lgx=t, $t^{2}+2t-3=0$

d. 25=x+3, x=22