Respuesta :

Answer:

The solution is x = 2 and x = 4

Step-by-step explanation:

Let us revise some rules in logarithmic function:

  • [tex]log_{a}(x)+log_{a}(y)=log_{a}(xy)[/tex]
  • The logarithmic function is the inverse of the exponential function
  • [tex]log_{b}(c)=a[/tex]  is the inverse of  [tex]b^{a}=c[/tex]

Let us solve the question

∵ [tex]log_{2}(x)+log_{2}(6-x)=3[/tex]

→ By using the first rule above

∴ [tex]log_{2}(x)(6-x)=3[/tex]

→ Multiply x by (6 - x)

∵ x(6 - x) = x(6) - x(x) = 6x - x²

∴ [tex]log_{2}(6x-x^{2})=3[/tex]

→ Change the logarithmic function to exponential function using

   the second rule above

∴ [tex]2^{3}=(6x-x^{2})[/tex]

∵ 2³ = 8

8 = 6x - x²

→ Add x² to both sides

∴ x² + 8 = 6x

→ Subtract 6x from both sides

∴ x² - 6x + 8 = 0

→ Factorize it into 2 brackets

(x - 2)(x - 4) = 0

→ Equate each factor by 0 to find the values of x

∵ x - 2 = 0

→ Add 2 to both sides

x = 2

∵ x - 4 = 0

→ Add 4 to both sides

x = 4

∴ The values of x are 2 and 4

The solution of the equation is x = 2 and x = 4