简化份数 (3^2008)^2-(3^2006)^2/(3^2007)^2-(3^2005)^2

问题描述:

简化份数 (3^2008)^2-(3^2006)^2/(3^2007)^2-(3^2005)^2
另外的是英文题 heather compares the price of a new computer at two different stores.store A offers 15% off the sticker price followed by a $90 rebate,and store B offers 25% off the sticker price with no rebate.heather saves $15 by buying the computer at store A instead of store B.what is the sticker price of the computer,in dollars?

(3^2008+3^2006)(3^2008-3^2006)/(3^2007+3^2005)(3^2007-3^2005)
=(3^2008+3^2006)*8*3^2006/(3^2007+3^2005)*8*3^2005
=(3^2008+3^2006)*3/(3^2007+3^2005)
=(27+3)*3/(9+1)=9
suppose the sticker price of the computer is x dollars
then the formula as the follow comes into existence
X*(1-15%)-90+15=X(1-25%)
so
x=750 dollars