作者LuisSantos ( )
看板trans_math
标题Re: [考古]求极限
时间Sun Jul 6 23:40:43 2008
※ 引述《reideen107 (理想一直都在)》之铭言：
: 1.Find the limit of the following questions,and give your reason.
: (1) lim |sin(x-2)| / x-2
: x→2
: (2) lim (x^1/3 (x+1)^2/3 -x)
: x→∞
lim ((x^(1/3))((x+1)^(2/3)) - x)
x→∞
(x)((x+1)^2) - x^3
= lim ------------------------------------------------------
x→∞ (x^(2/3))((x+1)^(4/3))+(x^(1/3))((x+1)^(2/3))(x) + x^2
(2)(x^2) + x
= lim ------------------------------------------------------
x→∞ (x^(2/3))((x+1)^(4/3))+(x^(1/3))((x+1)^(2/3))(x) + x^2
2 + (1/x)
= lim ------------------------------------------------
x→∞ (1 + 1/(x^(4/3)))^(4/3) + (1 + 1/(x^(2/3))) + 1
2 + 0
= ------------------------------------
(1 + 0)^(4/3) + (1 + 0)^(2/3) + 1
2 2
= ----------- = ---
1 + 1 + 1 3
: 另外
: 2. Find the curve of r=4cosθ
: 请问这题是求面积吗？
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1F：推 reideen107:请问一下，分母怎麽来的@@.有点笨 118.171.118.90 07/07 15:04