1+2的负八分之一次方)(1+2的负四分之一次方)(1+2的负二分之一次方)
=(1+2^-1/8)(1+2^-1/4)(1+2^-1/2)
=(1-2^-1/8)*(1+2^-1/8)(1+2^-1/4)(1+2^-1/2)/(1-2^-1/8)
=(1-2^-1/4)(1+2^-1/4)(1+2^-1/2)/(1-2^-1/8)
=(1-2^-1)/(1-2^-1/8)
=1/(2-2^7/8)
1+2的负八分之一次方)(1+2的负四分之一次方)(1+2的负二分之一次方)
=(1+2^-1/8)(1+2^-1/4)(1+2^-1/2)
=(1-2^-1/8)*(1+2^-1/8)(1+2^-1/4)(1+2^-1/2)/(1-2^-1/8)
=(1-2^-1/4)(1+2^-1/4)(1+2^-1/2)/(1-2^-1/8)
=(1-2^-1)/(1-2^-1/8)
=1/(2-2^7/8)