高一的指数幂的运算,计算题...
问题描述:
高一的指数幂的运算,计算题...
根号下的(a+2倍根号下a-1)+根号下(a-2倍根号a-1)(a大于等于1)
根号下(b-(2倍根号下b再-1)
3次根号下(2+根号5)+三次根号下(2-根号5)
答
[a+2(a-1)½]½+[a-2(a-1)½]½
=[((a-1)½)²+2(a-1)½+1]½+[((a-1)½)²-2(a-1)½+1]½
=(a-1)½+1+(a-1)½-1
=2(a-1)½
[b-2(b-1)½]½
=[((b-1)½)²-2(b-1)½+1]½
=(b-1)½
=1