1. 設(shè)函數(shù),則
在點(diǎn)
處的值為( ).
A. B.
C. D.
2. 曲線方程,則在
處法平面方程為( ).
A. B.
C. D.
3. 設(shè),則
在點(diǎn)
處( ).
A. 連續(xù)但偏導(dǎo)不存在 B. 偏導(dǎo)存在但不連續(xù)
C. 不可微 D. 偏導(dǎo)數(shù)連續(xù)
4. 設(shè),其中
,則( ).
A. B.
C. D.
5. 由四個(gè)平面所圍成的柱體被平面
截得的立體的體積是( ).
A. B. 1
C. D.
1.答案:B.解析:本題考查二元函數(shù)的混合偏導(dǎo)數(shù).
,
,
于是.(先對(duì)
求偏導(dǎo)后代入
值,再對(duì)
求偏導(dǎo)代入
值更節(jié)約時(shí)間).
2.答案:C.解析:本題考查曲線的法平面.
,
故法向量為,
故法平面為,即
.
3.答案:C.解析:本題考查多元函數(shù)的可微性.
因?yàn)?img height="30" src="data:image/wmf;base64,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" width="126" />,所以,故
在點(diǎn)
處連續(xù).
.
因?yàn)?img height="54" src="data:image/wmf;base64,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" width="426" />,
所以在點(diǎn)
處不可微.
4.答案:B.解析:本題考查比較二重積分的大小.
由于當(dāng)時(shí),
為減函數(shù),此時(shí)
,于是
,故
.
5.答案:C.解析:本題考查二重積分.
.
技巧:對(duì)稱性更節(jié)約時(shí)間.
推薦閱讀:
2025年軍隊(duì)文職人員公開招考咨詢服務(wù)電話和電子郵箱
推薦查看!
軍隊(duì)文職26年筆試網(wǎng)課 | 軍隊(duì)文職資料包 | 紅師師資助力考生 |
軍隊(duì)文職26年筆試課程 | 軍隊(duì)文職歷年考題 | 軍隊(duì)文職歷年分?jǐn)?shù) |