举一反三
- 以4,9,1为为插值节点,求\(\sqrt x \)的lagrange的插值多项式 A: \( {2 \over {15}}(x - 9)(x - 1) + {3 \over {40}}(x - 4)(x - 1) + {1 \over {24}}(x - 4)(x - 9)\) B: \( - {2 \over {15}}(x - 9)(x - 1) + {3 \over {40}}(x - 4)(x - 1) + {1 \over {24}}(x - 4)(x - 9)\) C: \( - {2 \over {15}}(x - 9)(x - 1) + {3 \over {40}}(x - 4)(x +1) + {1 \over {24}}(x - 4)(x - 9)\) D: \( - {2 \over {15}}(x - 9)(x - 1) + {3 \over {40}}(x - 4)(x - 1) - {1 \over {24}}(x - 4)(x - 9)\)
- 设[tex=5.857x1.286]/ZR0dAzaI7eKAw6bIvA7M58pHZGw+2OYCoei6GCt4jKnUA8fDz0Dp5V6q6Qe+E/Z[/tex],(1)求[tex=6.143x1.286]yawiFqFNRMZ/ZRG5pEYO2O+6TBLlt98eUoCA20JUzzI=[/tex],[tex=4.929x1.286]YYoux3kBOrr0oXG6Ruhoyw==[/tex],[tex=4.357x1.286]XVFgXYqJIcOWxMDF8fUe1A==[/tex];(2)确定[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex],使得[tex=9.929x1.286]bjnG7nzQo1uGLijNkCPTHU/v3I7Qw+oHtHefyp+/x0OcT++gNB916y9t0e7Qwq0v[/tex];(3)设[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]满足[tex=7.0x1.286]GlBMPwREMBtBPLKotOMDrnrbhevHLzxCxckRvPv1KoQ=[/tex],问[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]至多为多少?
- 前提:∀x(P(x)→Q(x)),∃xP(x) ⇒∃xQ(x) (1)∀x(P(x) → Q(x)) 前提 (2) ∃xP(x) 前提 (3) P(c) (2), Es规则 (4)P(c)→Q(c) (1), Us规则 (5) Q(c) (3)(4), 假言推理I (6)∃xQ(x) (5), Eg规则 上述推理过程是否正确?
- 求不定积分[img=115x46]17da65382f8e1b9.png[/img]; ( ) A: x - (5*log(x + 1))/4 - (3*log(x - 3)) B: (5*log(x + 1))/4 - (3*log(x - 3)) C: x - (5*log(x + 1))/4 - (3*log(x - 3))/4 D: (5*log(x + 1))/4 - (3*log(x - 3))/4
- 掷一枚均匀骰子,直到出现的点数小于3为止,记抛掷的次数为X,则以下结果正确的是 A: P(X=2)=2/9 B: P(X≥3)=4/9 C: P(X≤3)=19/27 D: P(X=1)=2/3 E: P(X≤2)=3/4 F: P(X=1)=1/2 G: P(X=2)=1/4 H: P(X<3)=7/8
内容
- 0
用谓词逻辑推理证明:有理数都是实数,有的有理数是整数,因此有的实数是整数。判断推理证明是否正确。 证明:设Q(x):x为有理数;R(x):x为实数;Z(x):x为整数; 前提:∀x(Q(x)→R(x)),∃x(Q(x)∧Z(x)); 结论:∃x(R(x)∧Z(x))。 (1)∃x(Q(x)∧Z(x)) 前提引入 (2)Q(c)∧Z(c) (1)∃- (3)∀x(Q(x)→R(x)) 前提引入 (4)Q(c)→R(c) (3)∀- ( 5 )Q(c) (2) 化简 ( 6 )R(c) (4)(5) 假言推理 ( 7 )Z(c) (2) 化简 (8)R(c)∧ Z(c) (6)(7) 合取引入 (9)∃x(R(x)∧Z(x)) (8)∃+
- 1
用谓词逻辑推理证明:有理数都是实数,有的有理数是整数,因此有的实数是整数。证明:设Q(x):x为有理数;R(x):x为实数;Z(x):x为整数;前提:∀x(Q(x)→R(x)),∃x(Q(x)∧Z(x));结论:∃x(R(x)∧Z(x))。(1)∃x(Q(x)∧Z(x))P(2)Q(c)∧Z(c)ES(1)(3)∀x(Q(x)→R(x))P(4)Q(c)→R(c)US(3)(5)Q(c)T(2)I(6)R(c)T(2)(4)I(7)Z(c)
- 2
函数的定义域是( ) A: {(x,|2<x2+y2<3} B: {(x,|4<x2+y2<9} C: {(x,|4<x2+y2≤9} D: {(x,|22+y2≤3}
- 3
某人对商品x的需求函数是[tex=5.214x1.214]0m6eBd5eyK0NjuxeKfwtIw==[/tex],[tex=4.214x1.214]I717YsPbj8Rnym1v2XQ+sFNkUl7mqUsGwbjwjXmy2xc=[/tex],这里[tex=0.571x1.0]Za328cIB4SeR7rrzY+MM5Q==[/tex]是[tex=0.571x0.786]ZSLOI4fiO1oAbVC5M8IVkA==[/tex]的价格。如果商品x 的价格是0.5元,那么他对商品x的需求价格弹性是 未知类型:{'options': ['-10', '- 1/5', '-1/10', '\xa0- 1/3'], 'type': 102}
- 4
设函数$y = f({x^3})$可导,求函数的二阶导数$y'' = $( ) A: $6xf'({x^3}) + 9{x^4}f''({x^3})$ B: $6f'({x^3}) + 9{x^3}f''({x^3})$ C: $6xf'({x^3}) + 9{x^3}f''({x^3})$ D: $6{x^2}f'({x^3}) + 9{x^3}f''({x^3})$