请教一下两道题

XIAOXIANGXI

请教一下这两个体的答案是怎么解出来的呢？

1， if (1/5)^m (1/4)^18 = 1/(2(10)^35)  then m = ?     答案：35  

2， if XY=1,  what's the value of (2(x+y)^2)/(2(x-y)^2) ?   答案：16

多谢

XIAOXIANGXI

pretty cool for the first one.  Thanks!

himba

QUOTE:

1， if (1/5)^m (1/4)^18 = 1/(2(10)^35)  then m = ?     答案：35 

 (1/5)^m (1/4)^18

=1/(5^m)*1/(2^36)

=1/[2(2^35)*(5^m)]

=1/(2(10)^35)

apparently, m=35

QUOTE:

2， if XY=1,  what's the value of (2(x+y)^2)/(2(x-y)^2) ? 

 

you can look up in GMAT-PREP讨论稿.

but as i know, there is something wrong in this question, so from the premise we have got we can not find the exact answer.