Could you help me to solve the maths problems?? thx~~
1.The length of a box is 15cm. If the precentage error is 4%, find
(a) the maximun error,
(b) the range of the actual length.
2.Factorize:
(a) 9a^2-b^2-6a+2b
maths problems(f.4)
2009-08-11 3:11 am
回答 (1)
2009-08-11 3:24 am
✔ 最佳答案
1a) the maximum error = 15 * 4% = + 0.6 cm or - 0.6cm
b) (15- 0.6)cm <= the range of the actual length <= (15+0.6)cm
14.4 cm <= the range of the actual length <= 15.6cm
2a) 9a^2-b^2-6a+2b
= (3a)^2 - b^2 - (6a - 2b)
= (3a - b)(3a + b) - 2(3a - b)
= (3a - b)(3a + b - 2)
收錄日期: 2021-04-21 22:02:47
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https://hk.answers.yahoo.com/question/index?qid=20090810000051KK01883