Answer:
[tex] {x}^{y} = {y}^{x} \: - - - (1)[/tex]
[tex]x = 2y \: - - - (2)[/tex]
Substitute (2) into (1):
[tex] {2y}^{y} = {y}^{2y} [/tex]
Log both sides:
[tex]lg(2 {y}^{y} ) = lg(y^{2y} )[/tex]
[tex]y \: lg(2y) = 2y(lg \: y)[/tex]
[tex]y \: lg(2) + y \: lg(y) = 2y \: lg(y)[/tex]
[tex]y \: lg(2) = 2y \: lg(y) - y \: lg(y)[/tex]
[tex]y \: lg(2) = y \: lg(y)[/tex]
Divide by y on both sides:
[tex]lg(2) = lg(y)[/tex]
[tex] {10}^{lg(2)} = {10}^{lg(y)} [/tex]
2= y
y= 2 (proved)
Explanation:
• step 5: lg(m)^n= nlg(m)
• Step 6: lg(mn)= lg(m) +lg(n)