Question

若x的1/2次方+x的负1/2=3 求（x的3/2次方+x负3/2-3）/（x的平方+x的负二次方-2）的值

Answer 1

解析:∵x^(1/2)+x^(-1/2)=3∴x+2+1/x=9,x+1/x=7∴x^2+2+x^(-2)=49∴x^2+x^(-2)=47[x^(3/2)+x^(-3/2)]/[x^2-2+x^(-2)]=[x^(1/2)+x^(-1/2)](x-1+1/x)/[x^2-2+x^(-2)]=3*(7-1)/(47-2)=18/45=2/52题：假设正方形DEFG的顶...