1、令log7(2根号2-1)+log2(根号2+1)=t,则log7(2根号2-1)+log2(根号2+1)+log7(2根号2+1)+log2(根号2-1)=log7[(2根号2)^-1]+log2[（根号2)^2-1]=1+0=t+a所以t=log7(2根号2-1)+log2(根号2+1)=1-a没办法.....只会做一题了.....
