(1+根号2)的2008次方×(1-根号2)的2009次方得多少啊?
问题描述:
(1+根号2)的2008次方×(1-根号2)的2009次方得多少啊?
答
=(1+√2)^2008*(1-√2)^2008*(1-√2)
=[(1+√2)(1-√2)]^2008*(1-√2)
=(-1)^2008*(1-√2)
=1-√2
答
(1+√2)^2008*(1-√2)^2009
=(1+√2)^2008*(1-√2)^2008*(1-√2)
=[(1+√2*(1-√2)]^2008*(1-√2)
=[(1-2)]^2008*(1-√2)
=[(-1)]^2008*(1-√2)
=(1-√2)