Given that log x= 5 and log y= -7. Evaluate the following :

a) log xy.
b) log 1/x.
c) log y/x.
d) log xy^2.

4 answers

a
log x y = log x + log y = -2

b
10^log x = x
10^0 = 1
so
log 0 = 1
so now the problem
log 1/x = log 1 - log x = 0 - log x = -log x = -5

c.
log y - log x obviously
-7 - 5 = - 12

d.
log x + 2 log y
5 + 2(-7) = 5 - 14 = -9
LOL

I mean log 1 = 0 !!!!!!
Thanks
You are welcome .