Dec 14, 2013 · Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack ExchangeWomen. Both. Shop the b+ab collection at ITeSHOP Hong Kong. Grab the latest b+ab jackets, dresses and cardigans. Don't miss out.Feb 14, 2022 · Published on February 14, 2022. Key takeaways: There are four blood types: A, B, AB, and O. Each blood type also has a positive or negative. Some blood types are more common than others. People with rare blood types might have trouble finding a match for a blood transfusion. Mar 15, 2024 · The IB Predict calculator absolutely does not lie. It uses grade boundary data from past IB examinations to ensure precision. With IB Predict, you'll know exactly what is needed in order to score a 4, 5, 6, or 7. No more, no less. 👀Announcement👀. I have updated the site with November 2023 grade boundaries.In A/B testing, A refers to ‘control’ or the original testing variable. Whereas B refers to ‘variation’ or a new version of the original testing variable. The version that moves your business metric (s) in the positive direction is known as the ‘winner.’. Implementing the changes of this winning variation on your tested page (s ...Boolean Algebra Calculator. Select text and press '!' to Not the selection. Press '+' for an 'or' gate. Eg; A+B. Press '!' to insert a 'not' gate. Side by side characters represents an 'and' gate. Eg; AB+CA. The boolean algebra calculator is an expression simplifier for simplifying algebraic expressions. It is used for finding the …Oct 11, 2020 · I didn't find (a+b)* = (ab)* in rules of regular expressions. regular-languages; finite-automata; regular-expressions; Share. Cite. Improve this question. Follow asked Oct 11, 2020 at 5:51. mehant_kr mehant_kr. 1 1 1 gold badge 1 1 silver badge 1 1 bronze badge $\endgroup$ 3. 2Nov 23, 2017 · 所以 AB=O 不能推出 A=O\text { or } B=O. 当然同样的，明确了A可逆，那么有B为O.. 实数公理的一部分是实数构成一个域，简单来说也就是对加减乘除封闭。. 当b不为0时，两边同乘以b的乘法逆元，得到a=0，因此b不为0则a为0，这等效于b为0或a为0. 昨天指导弟弟解答一个 ...Nov 3, 2016 · 纯天然实木地板的缺点：它的价格比较高，而且比较难保养，天气潮湿或干燥时容易起拱、翘曲或变形。. 实木地板分A板，AB板，B板，这三种板中A板最好，当然价格也是最高的，它是属于是高端板，AB板是主流，市面上大部分品牌的都是AB板，还有一 …Jul 22, 2019 · 血型主要分为四种：A、B、AB、O型四种。O型血又被称为“万能血”，因为前三种血型的人如果需要输血的话，都是可以接受O型血的，但是O型血的人只能接受O型血。还有一种平时很罕见，大部分人都只能在电视上看到的RH ...Nov 9, 2019 · 你敢说没这可能？. 其实还真是有A或B不得不为零的情况。. 比如A不为零，且满秩，以上矩阵乘法其实就变成n个齐次方程组，把C=AB拆开，得到：. c₁=Ab₁=0. c₂=Ab₂=0. …. cₙ=Abₙ=0. 其中cₓ和bₓ都是向量，这就是n个齐次方程组。. 一个齐次方程组在A满秩时就只有 ...Aug 17, 2022 · 显然满足 P (AB)=P (A)P (B) ，A的发生，不影响B的概率，B的发生也不影响A的概率。. 但是已知A发生的条件下，显然B中的1和3直接排除了可能。. 所以说，上面的例子，说明了要把语文or现实意义上的互不影响和 概率论 意义上的事件独立区分。. 那么， P (A)=1 ， 事件A ...Jun 8, 2023 · Misc 2 Show that the matrix B’AB is symmetric or skew symmetric according as A is symmetric or skew symmetric. We need to prove B’AB is symmetric if A is symmetric and B’AB is skew symmetric if A is skew symmetric Proving B’AB is symmetric if A is symmetric Let A be a symmetric mJan 23, 2023 · An amplifier is an electronic device used to increase the magnitude of voltage/current/power of an input signal. It takes in a weak electrical signal/waveform and reproduces a similar stronger waveform at the output by using an external power source. Depending on the changes it makes to the input signal, amplifiers are …Apr 1, 2018 · 不难看出Col (AB)为Col (A)的子集，. 于是dimCol (AB)<=dimCol (A)，即rank (AB)<=rank (A). 同理rank (B’A’)<=rank (B’)，利用rank (M)=rank (M’)，立得rank (AB)<=rank (B). 编辑于 2023-10-10 20:01. 知乎，中文互联网高质量的问答社区和创作者聚集的原创内容平台，于 2011 年 1 月正式上线 ...Mar 29, 2020 · 解高维微分方程的一个问题，有没有数学大佬了解 若 AB = BA ，则 e^{A+B} =e^{A}e^{B} Proof: e^{A+B} = \sum_{n = 0}^{+\infty}\frac{(A+B)^n}{n ...Shop for B+ AB clothing for women at Lyst.com, a fashion platform that offers free shipping and returns. Find tweed, cardigan, dress, jacket and more from B+ AB at discounted prices.Sep 6, 2016 · I am trying to understand the simplification of the boolean expression: AB + A'C + BC. I know it simplifies to. A'C + BC. And I understand why, but I cannot figure out how to perform the simplification through the expression using the boolean algebra identities.Sep 6, 2016 · I am trying to understand the simplification of the boolean expression: AB + A'C + BC. I know it simplifies to. A'C + BC. And I understand why, but I cannot figure out how to perform the simplification through the expression using the boolean algebra identities.Oct 26, 2020 · 构造 A (I-BA) = A-ABA=A-A=0 , 立刻得到 I-BA=0 . 即 BA=I \quad \square . 需要看矩阵A.矩阵B是否可逆，可逆就行否则不行. 特征值一个问题是无论是由行列式还是向量来反推矩阵的关系是很难的。. 虽然在一般的情况下ab=1并不能得到ba=1，但矩阵是个特例，我提供了一个比较 ...Nov 17, 2006 · Someone who has an A and a B version of the blood type gene makes both A and B proteins. And so is AB blood type. But someone who has a B and an O version only makes the B protein. They are B blood type but can pass the O onto their kids. So two B parents can make an O child if both parents are BO.Jul 22, 2019 · 血型主要分为四种：A、B、AB、O型四种。O型血又被称为“万能血”，因为前三种血型的人如果需要输血的话，都是可以接受O型血的，但是O型血的人只能接受O型血。还有一种平时很罕见，大部分人都只能在电视上看到的RH ...Mar 24, 2020 · 矩阵乘积的秩. 矩阵乘积 AB 的秩和矩阵 A,B 的秩有什么关系呢？. 首先直观上说明。. 线性映射 Ax = y ，当矩阵 A 是列满秩矩阵时，即无关组时，映射是单射，所以定义域内一个向量 x 对应值域内一个向量 y ，值域内一个向量 y 也对应定义域内一个向量 x ，或者说 ...Mar 15, 2024 · The IB Predict calculator absolutely does not lie. It uses grade boundary data from past IB examinations to ensure precision. With IB Predict, you'll know exactly what is needed in order to score a 4, 5, 6, or 7. No more, no less. 👀Announcement👀. I have updated the site with November 2023 grade boundaries.Feb 26, 2016 · C语言文件打开模式浅析 在C语言的文件操作语法中，打开文件文件有以下12种模式，如下图： 打开模式 只可以读 只可以写 读写兼备 文本模式 r w a r+ w+ a+ 二进制模式 rb wb ab rb+ (r+b) wb+ (w+b) ab+ (a+b) 其中，二进制模式与文本模式操作相似，只不.Mar 29, 2023 · 符号说明： A ， B ： n 阶矩阵 A' ： A 的转置. 正文： 以下几个等式一般不成立(AB)^m=A^mB^m，m\in\mathbb Z^+.(A+B)^2=A^2+2AB+B^2，A^2-B^2 ...Nov 9, 2019 · 你敢说没这可能？. 其实还真是有A或B不得不为零的情况。. 比如A不为零，且满秩，以上矩阵乘法其实就变成n个齐次方程组，把C=AB拆开，得到：. c₁=Ab₁=0. c₂=Ab₂=0. …. cₙ=Abₙ=0. 其中cₓ和bₓ都是向量，这就是n个齐次方程组。. 一个齐次方程组在A满秩时就只有 ...Dec 11, 2018 · Class C amplifier is tuned amplifier which works in two different operating modes, tuned or untuned. The efficiency of Class C amplifier is much more than the A, B, and AB. Maximum 80% …表切余 题命假式数对,律定理查B电流直caiaugrehsugB=1.ton tessug SeFShop Women's B+ AB Tops. 122 items on sale from $40. Widest selection of New Season & Sale only at Lyst.com. Free Shipping & Returns available.Oct 22, 2019 · 第一部分 知识积累一、公式 1.两集合 A+B-AB=总数一都不 2.三集合 A+B+C-AB-AC-BC+ABC=总数一都不 A+B+C-满足两项一满足三项×2=总数一都不 满足一项+满足两项+满足三项=总数一都不 2.画图 ①画圈圈，…Feb 18, 2020 · 酸碱中毒中AB、SB、BB、BE各代表什么？. 为了帮助大家了解，医学教育网为大家整理如下：. 1.AB（即实际碳酸氢盐）：是指隔绝空气的全血标本，在实际状况下测得的血浆碳酸氢盐的量。. （正常值为22-27mmol/L）。. 既是反映代谢因素的指标，又是反映呼吸因素的 ...Mar 15, 2024 · The IB Predict calculator absolutely does not lie. It uses grade boundary data from past IB examinations to ensure precision. With IB Predict, you'll know exactly what is needed in order to score a 4, 5, 6, or 7. No more, no less. 👀Announcement👀. I have updated the site with November 2023 grade boundaries.3 days ago · The XOR or Exclusive OR Gate is a special type of logic gate used in digital electronics to perform the exclusive OR operation. The XOR gate takes two inputs and produces an output depending on the combination of the two inputs applied. In, this article will explain the complete theory of the XOR gate along with its truth table, boolean …Jun 2, 2015 · 按题主的意思是说：方阵AB=方阵BA，那么他们的 特征向量 （请注意特征向量一定非零）相等同时迹也相等。. 但是很明显的反例就是取 A=\left [ 1~~~1\right] ^ {T} B=\left [2~~~0\right] ，那么AB无特征向量，而BA有特征向量1。. 更一般的有，AB和BA的对应的特征向量的维数都 ...b+ab clothing encourages boundaryless self-expression. Merging timeless fabrics and clean-cut silhouettes, the Hong Kong brand redefines how identity can be decoded and recoded through …Women. Both. Shop the b+ab collection at ITeSHOP Hong Kong. Grab the latest b+ab jackets, dresses and cardigans. Don't miss out.Object moved to here.b+ab is a brand that offers trendy and affordable women's clothing, such as dresses, tops, skirts, and sets. Browse their products and shop online on Facebook.4 days ago · Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack Exchange显著性差异a和ab怎么解释. 圆梦之灵. 2021-07-22 23431人看过. 04:02. 只要含有相同的字母，就表明两组之间没有显著性差异。. a和ab含有相同字母“a”，表示两组之间没有显著性差异。. ab中的“b”表示这一组和其他含有字母b的组（比如bc）没有显著性差异，但是a和bc ...Jun 7, 2016 · 第4章词法分析作业参考答案. 系统标签：. 词法分析 dfa 答案 nfa 作业 quz. 章词法分析作业参考答案4.7练习（P72）1．构造下列正规式相应的DFA：b ( (ab)*|bb)*ab解：先将正规式转换为NFA，转换过程如下：以下为最终所得的NFA然后，将此NFA转换为DFA：转换关系矩阵如下 ...Sep 18, 2015 · Given an m × n m × n -matrix A A and an n × p n × p -matrix B B. Prove that (AB)T = BTAT ( A B) T = B T A T. Here is my attempt: Write the matrices A A and B B as A = [aij] A = [ a i j] and B = [bij] B = [ b i j], meaning that their (i, j) ( i, j) -th entries are aij a i j and bij b i j, respectively. Let C = AB = [cij] C = A B = [ c i j ...Mar 29, 2020 · 解高维微分方程的一个问题，有没有数学大佬了解 若 AB = BA ，则 e^{A+B} =e^{A}e^{B} Proof: e^{A+B} = \sum_{n = 0}^{+\infty}\frac{(A+B)^n}{n ...Jun 16, 2020 · 01拓展一：a+b+c ≥√ab+√ac+√bc. 证明：a+b+c=1/2 (a+b+a+c+b+c)，. 根据基本不等式a+b≥2√ab，. 所以a+b+c≥1/2 (2√ab+2√ac+2√bc)，. 所以有a+b+c≥√ab+√ac+√bc成立，. 当且仅当a=b=c时等号成立，a，b，c∈R+。. 02拓展二：a+b+c+d≥2/3 (√ab+√ac+√ad+√bc+√bd+√cd) 同理 …Mar 23, 2024 · The 4 blood types are A, B, AB, and O. Physiologically, your blood type refers to the types of antigens (protein molecules that trigger immune responses) found on your red blood cells. There’s no scientific evidence that blood type has a measurable effect on personality, although some researchers …Apr 20, 2021 · An OR gate with two complemented inputs is equivalent to a NAND gate (according to DeMorgan’s Law A’+B’ = (AB)’). Hence, replacing the OR gate, which is having two complemented inputs, with NAND gate, we get the final structure of the implementation of the Boolean function using NAND gates. The final implementation is shown below.b+ab for Women. Prepare to push boundaries with b+ab. The contemporary Asian label hails from Hong Kong and takes inspiration from algebraic expressions — redefining how identity can be …Keeping people and society safe. Saab serves the global market of governments, authorities and corporations with products, services and solutions ranging from military defence to civil security. Saab AB (publ), SE-581 88 Linköping, Sweden, Reg No 556036-0793. Saab serves the global market of governments, authorities and …May 27, 2015 · 先从算数平均数. 说起， 算数平均数 可以理解为长为 a 和 b 两条线段和的一半，即是线段和（总长）被平均分成两份，如图：. 由此联想，什么什么的平均可能是某种平均分的关系，进而 联想几何 平均可能是几何上与 a, b 有关的曲线被平均分了 ，现在来看 几何 ...Was £16.99. £11.99. Save £5.00. £1.20 / l. Add to basket. *Read our terms & conditions here. See our product recalls and safety notices. Spring Sale now on, shop everything you need for your Spring home projects. Order online for 1hr Click+Collect, or free home delivery on orders over £75.2 days ago · 网站 A/B 测试的优势 网站 A/B 测试可量化展示哪种营销策略对网站访客最有效，助您轻松验证一项直觉是正确还是错误。除此之外，您还可以排除无效选项，吸引更多访客在您的网站上花费更多时间，点击更多链接。b+ab is a Hong Kong-based fashion brand that offers quality products in sensible price-points for women across generations. It has two lines, ‘Main Line’ and ‘Pink Label’, that create a spectrum of available styles for women with individual …Feb 26, 2020 · 设A是数域上的一个n阶矩阵，若在相同数域上存在另一个n阶矩阵B，使得： AB=BA=E ，则我们称B是A的逆矩阵，而A则被称为可逆矩阵。. 注：E为单位矩阵。. （1）求逆矩阵的初等变换法：. 将一n阶可逆矩阵A和n阶单位矩阵I写成一个nX2n的矩阵. 对B施行初等行变换，即 ...It's the XNOR function, which typically doesn't occur often enough to warrant its own operator. It's the negation of XOR, though, which can be seen by applying De Morgan's law …Mar 16, 2017 · 经常说A，B，AB，O型血，其实不光AB血型是两个字母，其它血型也是由两个字母。 比如你是A型血，其实是AO型血或者AA型血；B型血其实是BO或者BB；O型血其实是OO；但因为只有O属于隐性基因，太弱小，A和B属于显性基因，都太彪悍，所以O与A、B一起出现时，O被可以无视。Jan 2, 2005 · 以下内容是CSDN社区关于AB=0,那么|A|=0或|B|=0?(线数基础问题)相关内容，如果想了解更多关于数据结构与算法社区其他内容，请访问CSDN社区。Mar 21, 2024 · 网络不给力，请稍后重试Jan 2, 2005 · 以下内容是CSDN社区关于AB=0,那么|A|=0或|B|=0?(线数基础问题)相关内容，如果想了解更多关于数据结构与算法社区其他内容，请访问CSDN社区。Aug 17, 2022 · 显然满足 P (AB)=P (A)P (B) ，A的发生，不影响B的概率，B的发生也不影响A的概率。. 但是已知A发生的条件下，显然B中的1和3直接排除了可能。. 所以说，上面的例子，说明了要把语文or现实意义上的互不影响和 概率论 意义上的事件独立区分。. 那么， P (A)=1 ， 事件A ...Nov 28, 2023 · The blood types are A, B, AB, and O. The Rh factor makes them either positive or negative. Blood types are a classification of blood based on the presence or absence of specific antigens on the surface of red blood cells. These antigens determine the body’s immune response to foreign substances and are crucial in the context of blood …表切余 题命假式数对,律定理查B电流直caiaugrehsugB=1.ton tessug SeFApr 20, 2021 · An OR gate with two complemented inputs is equivalent to a NAND gate (according to DeMorgan’s Law A’+B’ = (AB)’). Hence, replacing the OR gate, which is having two complemented inputs, with NAND gate, we get the final structure of the implementation of the Boolean function using NAND gates. The final implementation is shown below.Amplifier classes are mainly lumped into two basic groups. The first are the classically controlled conduction angle amplifiers forming the more common amplifier classes of A, B, AB and C, which are defined by the length of their conduction state over some portion of the output waveform, such that the output stage transistor operation lies somewhere …Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, just like a math tutor.Jun 8, 2023 · Misc 2 Show that the matrix B’AB is symmetric or skew symmetric according as A is symmetric or skew symmetric. We need to prove B’AB is symmetric if A is symmetric and B’AB is skew symmetric if A is skew symmetric Proving B’AB is symmetric if A is symmetric Let A be a symmetric mHealthy employees benefit your business. Give your employees an expertly designed plan made for them—and for your business. Whether you have 2 or 2,000 employees, Alberta Blue Cross ® offers flexible and cost-sustainable options. Choose from health and dental benefits, life insurance options and more to create a customized plan that meets your …AB: [noun] the one of the four ABO blood groups characterized by the presence of antigens designated by the letters A and B and by the absence of antibodies against these antigens.表切余 题命假式数对,律定理查B电流直caiaugrehsugB=1.ton tessug SeFJan 30, 2024 · Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack ExchangeJan 25, 2019 · 今天在刷LeetCode的时候遇见了一道题，题的要求是“给你一个整数n，按字典序返回范围[1, n]内所有整数。你必须设计一个时间复杂度为O(n)且使用O(1)额外空间的算法。”开始以为是简单的输出，提交后发现与答案相差甚多，看评论后方了解按字典序是什么意 目录 一、何为字典序 二、解题步骤 1.1-n ...Nov 4, 2023 · Then the amplifier classes are always defined as follows: Class A: – The amplifiers single output transistor conducts for the full 360 o of the cycle of the input waveform. Class B: – …Sep 25, 2020 · 已知 (a, b) = 1，求证 (a + b, ab) = 1 。感觉是显而易见的结论，但是就是不知道怎么证。没学过数论，如… 首页 知乎知学堂 发现 等你来答 切换模式 登录/注册 数学 数论 素数 初等数论 ...Nov 28, 2023 · The ABO blood group system is the primary blood type classification system. It categorizes blood into four main types: Type A: Has A antigens on the red cells and anti-B antibodies in the plasma. Type B: Has B antigens with anti-A antibodies in the plasma. Type AB: Has both A and B antigens, but no anti-A or anti-B antibodies. Oct 5, 2022 · 以后买手机一定买相机好的，不然拍个照片，很多文字都是虚的，模糊的，我拍了好久才拍清楚的。推论Jun 8, 2023 · A类 A类放大器是最简单的放大器类型，对于任何输出波形，其输出级的晶体管始终处于导通状态(不会完全关断)。这类放大器具有极佳的线性特性，但效率很低。 B类 B类放大器的输出级晶体管只在信号波形的半个周期(180度)导通，为了对整个信号进行放大，使用了两个晶体管，一个用于正输出信号 ...Nov 17, 2006 · Someone who has an A and a B version of the blood type gene makes both A and B proteins. And so is AB blood type. But someone who has a B and an O version only makes the B protein. They are B blood type but can pass the O onto their kids. So two B parents can make an O child if both parents are BO.Nov 16, 2020 · 看题主的问题和图片，应该是micro USB接口，这算是目前常见的接口了，有分为AB型、B型。. Micro-USB连接器比标准USB和Mini-USB连接器更小，节省空间，具体的AB型和B型接口如下：. 市面上还是有很多Micro USB转USB接头的U盘，左边的Micro USB的接头，右边则是普通USB的接头 ...Mar 9, 2018 · a.ab和b.ab大小差不多，其中纹理资源比较大，所以可以肯定a.ab中也包含了一份d。 接下来看运行时加载效果，只加载a.ab并实例化a预设后： Cube显示正常，Capsule丢失材质：说明a.ab中包含了材质c和贴图d，不包含材质b，符合预测。
Nov 28, 2023 · The blood types are A, B, AB, and O. The Rh factor makes them either positive or negative. Blood types are a classification of blood based on the presence or absence of specific antigens on the surface of red blood cells. These antigens determine the body’s immune response to foreign substances and are crucial in the context of blood …. Ink and alloy
Feb 24, 2012 · Truth tables list the output of a particular digital logic circuit for all the possible combinations of its inputs. The truth table of an XOR gate is given below: The above truth table’s binary operation is known as exclusive OR operation. It is represented as A ⊕ B. The symbol of exclusive OR operation is represented by a plus ring …Aug 12, 2022 · 其中，A类放大器是具有高线性度的高增益放大器，用于小信号、低噪声；AB类放大器结合了A类放大器和B类放大器的优点，产生了更好的放大器设计；B类和C类放大器具有高功率效率和输出信号的高谐波含量，需要外部混频电路或 滤波电路 ；D类放大器工作于脉宽 ...Nov 27, 2021 · 如此类推，算术-几何均值不等式由此得名！三、基本不等式成立的前提 1）一正：a、b必须是正数 ∵ \frac{a+b}{2}\geq\sqrt{ab} 中，①若a、b为负数，则 \frac{a+b}{2}＜0 ，不等式不成立；②若a、b为异号，则 \sqrt{ab} 无意义；∴a、b必须为正数 2）二定： ...Feb 9, 2024 · Now take that result and multiply by a+b again: (a 2 + 2ab + b 2 ) (a+b) = a3 + 3a2b + 3ab2 + b3. And again: (a 3 + 3a 2 b + 3ab 2 + b 3 ) (a+b) = a4 + 4a3b + 6a2b2 + 4ab3 + b4. The calculations get longer and longer as we go, but there is some kind of pattern developing. That pattern is summed up by the Binomial …Mar 23, 2024 · The 4 blood types are A, B, AB, and O. Physiologically, your blood type refers to the types of antigens (protein molecules that trigger immune responses) found on your red blood cells. There’s no scientific evidence that blood type has a measurable effect on personality, although some researchers …Phys. Rev. B 54, 11169 (1996) - Efficient iterative schemes for ab ...3 days ago · The XOR or Exclusive OR Gate is a special type of logic gate used in digital electronics to perform the exclusive OR operation. The XOR gate takes two inputs and produces an output depending on the combination of the two inputs applied. In, this article will explain the complete theory of the XOR gate along with its truth table, boolean …Feb 26, 2024 · The chord is often abbreviated as Abm. Abm stands for A flat minor. Theory: The Ab minor chord is constructed with a root, a minor third An interval consisting of three semitones, the 3rd scale degree and a perfect fifth An interval consisting of seven semitones, the 5th scale degree. Fingerings: Little finger, middle finger, thumb (left hand ...Feb 26, 2016 · C语言文件打开模式浅析 在C语言的文件操作语法中，打开文件文件有以下12种模式，如下图： 打开模式 只可以读 只可以写 读写兼备 文本模式 r w a r+ w+ a+ 二进制模式 rb wb ab rb+ (r+b) wb+ (w+b) ab+ (a+b) 其中，二进制模式与文本模式操作相似，只不.Mar 21, 2024 · 网络不给力，请稍后重试Feb 1, 2024 · So, basically I'm taking an intro into proofs class, and we're given homework to prove something in abstract algebra. Being one that hasn't yet taken an abstract algebra course I really don't know ifAug 18, 2016 · 逻辑运算 的乘号代表与，加号代表是或，所以第一步. （A+B）（A+C）=AA+AB+AC+BC完全合理，实在不行就分开（A+B）A+C（A+B）. 可以当成一个事件对A C两个事件分别求同时成立的条件. 然后再想，而 AA+AB+AC=A 这一步用到的A（1+B+C）=a是因为这时b和c和1. 变成或的关系啦 ....