Question

x2 + y2= 25xy, then prove that 2 log(x+y)=3log3+logx+logy

Answer 1

See this photo, you will get the answer

Answer 2

Solutions 

x²+y²=25xy

Start with adding 2xy on both sides of the given equation 

x²+y²+2xy=27xy

Simplify 

[x+y]²=27xy

Now take log on both sides 

log[x+y]²=log27xy

2log[x+y]=log3³+log x+log y

2 log[x+y]=3log3+logx+logy