一道美国数学题 Factor each of th

5个回答

分子分母同乘以√(x+1)√(x-1)即√(x²-1)
= [√(x-1)√(x-1) - √(x+1)√(x+1)]/[2(x-1)√(x²-1)]
= [(x-1) - (x+1)]/[2(x-1)√(x²-1)]
= -1/[(x-1)√(x²-1)]
It's not easy to type fractions as superscript,so square root was used instead.