simplify the expressions and express the answer in positive index
a^(-2) - b^(-2)
a - b
maths f.4
2011-02-14 3:00 am
回答 (1)
2011-02-14 3:12 am
✔ 最佳答案
a^(-2) - b^(-2)= 1/a^2 - 1/b^2
= (b^2 - a^2)/(a^2 b^2)
= (b - a)(b + a)/(a^2 b^2)
a^(-2) - b^(-2)
a - b
= [(b - a)(b + a)]/[(a^2 b^2)(a - b)]
= -(b + a)/(a^2 b^2)
收錄日期: 2021-04-23 20:43:34
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