请用平方差公式运算.①（1+1/2)(1+1/2²)(1+1/2^4)(1+1/2^8)+1/2^15=?②（

①（1+1/2)(1+1/2²)(1+1/2^4)(1+1/2^8)+1/2^15
=(1-1/2)（1+1/2)(1+1/2²)(1+1/2^4)(1+1/2^8)/(1-1/2)+1/2^15
=(1-/2^16)*2+1/2^15
=2
②（1-1/2²）（1-1/3²)(1-1/4²)……(1-1/10²)
=(1-1/2)(1+1/2)(1-1/3)(1+1/3)(1-1/4)(1+1/4).(1-1/10)(1+1/10)
=1/2*3/2*2/3*4/3*3/4*5/4*.*9/10*11/10
=1/2*11/20
=11/40