Latex相关用法

Latex相关用法

样式			LaTex
[ 		$\begin{bmatrix}$ :代表左侧方括号 

]		$\end{bmatrix}$	  :代表右侧方括号

$\cdots$:代表水平省略号
 
$\vdots$:代表竖直省略号

$\ddots$:代表对角省略号

\(\cdots\):代表水平省略号

\(\vdots\):代表竖直省略号

\(\ddots\):代表对角省略号

1.字母和符号

1.1 数学中字母样式

${AaBbCc}$   			斜体,大部分数学符号、表达式
$ \mathrm{AaBbCc}$		正体、公式中的单位或文字
$ \mathbf{AaBbCc}$		粗体、向量、矩阵
$ \boldsymbol{AaBbCc}$	粗体、斜体、向量、矩阵
$ \mathtt{AaBbCc}$		等宽字体、常用于代码
$\mathcal{ABCDEF}$		花体,用于表示数学中的集合、代数结构、算子
$\mathbb{CRQZN}$		黑板粗体,常用来表达各种集合
$\text{Aa Bb Cc}$		用来写公式中的文字
$\mathrm{d}x$			ISO规定导数符号d为正体
$\operatorname{T}$		运算符

相关样式展示

  1. \({AaBbCc}\) 斜体,大部分数学符号、表达式
  2. $ \mathrm{AaBbCc}$ 正体、公式中的单位或文字
  3. $ \mathbf{AaBbCc}$ 粗体、向量、矩阵
  4. $ \boldsymbol{AaBbCc}$ 粗体、斜体、向量、矩阵
  5. $ \mathtt{AaBbCc}$ 等宽字体、常用于代码
  6. \(\mathcal{ABCDEF}\) 花体,用于表示数学中的集合、代数结构、算子
  7. \(\mathbb{CRQZN}\) 黑板粗体,常用来表达各种集合
  8. \(\text{Aa Bb Cc}\) 用来写公式中的文字
  9. \(\mathrm{d}x\) ISO规定导数符号d为正体
  10. \(\operatorname{T}\) 运算符

1.2 数学中字母标记

$x'$					x prime								x的导数
$x^{\prime}$  			x prime								x的导数
$x'’$					x double prime						x的二次导数
$\overrightarrow{AB}$	a vector pointing from A to B		向量AB
$\underline{x}$			x underline							x下
$\hat{x}$				x hat								x帽
$\bar{x}$				x bar								x把
$\dot{x}$				x dot								x点
$\tilde{x}$				x tilde								x波浪
$x_i$					x subscript i, x sub i				xi
$x^i$					x to the							x的i次方
$\ddot{x}$				x double dot						x双点
$x^*$					x star, x super asterisk			x星
$x\dagger$				x dagger							**转置+共轭**‌的复合操作‌
$x\ddagger$				x double dagger						**转置+共轭**‌的复合操作‌
${\color{red}x}$		red x								红x

相关样式展示

  1. \(x'\) x的导数
  2. \(x^{\prime}\) x的导数
  3. \(x'’\) x的二次导数
  4. \(\overrightarrow{AB}\) 向量AB
  5. \(\underline{x}\) x下
  6. \(\hat{x}\) x帽
  7. \(\bar{x}\) x把
  8. \(\dot{x}\) x点
  9. \(\tilde{x}\) x波浪
  10. \(x_i\) xi
  11. \(x^i\) x的i次方
  12. \(\ddot{x}\) x双点
  13. \(x^*\) x星
  14. \(x\dagger\) 转置+共轭‌的复合操作‌
  15. \(x\ddagger\) 转置+共轭‌的复合操作‌
  16. \({\color{red}x}\) 红x

1.3 希腊字母

小写 		LaTex 		 大写 	LaTex 		英文拼写 		发音
α 		$\alpha$ 	  	Α 		$A$ 		alpha 		/ˈælfə/
β 		$\beta$ 	 	Β 		$B$ 		beta 		/ˈbeɪtə/
γ 		$\gamma$ 	  	Γ 		$\Gamma$ 	gamma 		/ˈɡæmə/
δ 		$\delta$ 	  	Δ 		$\Delta$ 	delta 		/ˈdeltə/
ε 		$\epsilon$ 	  	Ε 		$E$ 		epsilon 	/ˈepsɪlɑːn/
ζ 		$\zeta$ 		Ζ 		$Z$ 		zeta 		/ˈziːtə/
η 		$\eta$ 			Η 		$H$ 		eta 		/ˈiːtə/
θ 		$\theta$ 		Θ 		$\Theta$ 	theta 		/ˈθiːtə/
ι 		$\iota$ 		Ι 		$I$ 		iota 		/aɪˈoʊtə/
κ 		$\kappa$ 		Κ 		$K$ 		kappa 		/ˈkæpə/
λ 		$\lambda$ 		Λ 		$\Lambda$ 	lambda 		/ˈlæmdə/
μ 		$\mu$ 			Μ 		$M$ 		mu 			/mjuː/
ν 		$\nu$ 			Ν 		$N$ 		nu 			/njuː/
ξ 		$\xi$ 			Ξ 		$\Xi$ 		xi 			/ksaɪ/ 或 /zaɪ/ 或 /ɡzaɪ/
ο 		$\omicron$ 		Ο 		$O$ 		omicron 	/ˈɑːməkrɑːn/
π 		$\pi$ 			Π 		$\Pi$ 		pi 			/paɪ/
ρ 		$\rho$ 			Ρ 		$P$ 		rho 		/roʊ/
σ 		$\sigma$ 		Σ 		$\Sigma$ 	sigma 		/ˈsɪɡmə/
τ 		$\tau$ 			Τ 		$T$ 		tau 		/taʊ/
υ 		$\upsilon$ 		Υ 		$Y$ 		upsilon 	/ˈʊpsɪlɑːn/
φ 		$\phi$ 			Φ 		$\Phi$ 		phi 		/faɪ/
χ 		$\chi$ 			Χ 		$X$ 		chi 		/kaɪ/
ψ 		$\psi$ 			Ψ 		$\Psi$ 		psi 		/saɪ/
ω 		$\omega$ 		Ω 		$\Omega$ 	omega 		/oʊˈmeɡə/

1.4 希腊字母,变量

LaTeX写法
$\vartheta$
$\varrho$
$\varkappa$ 
$\varphi$
$\varpi$
$\varepsilon$
$\varsigma$

相关样式展示

  1. \(\vartheta\)
  2. \(\varrho\)
  3. \(\varkappa\)
  4. \(\varphi\)
  5. \(\varpi\)
  6. \(\varepsilon\)
  7. \(\varsigma\)

1.5 常用符号

LaTex 				英文读法 				中文表达
$\times$ 		multiplies, times 			乘
$\div$			divided by 					除以
$\otimes$		tensor product 				张量积
$($				left parenthesis			左圆括号
$)$				right parenthesis			右圆括号
$[$				left square bracket			左方括号
$]$				right square bracket		右方括号
$\{$			left brace					左大括号
$\}$			right brace					右大括号
$\pm$			plus or minus 				正负号
$\mp$ 			minus or plus 				负正号
$<$				less than 					小于
$\leq$			less than or equal to 		小于等于
$\ll$ 			much less than 				远小于
$>$				greater than 				大于号
$\geq$			greater than or equal to 	大于等于
$\gg$ 			much greater than 			远大于
$=$				equals, is equal to 		等于
$\equiv$		is identical to 			完全相等
$\approx$		is approximately equal to 	约等于
$\propto$		proportional to 			正比于
$\partial$		partial derivative 			偏导
$\nabla$		del, nabla 					梯度算子
$\infty$		infinity 					无穷
$\neq$			does not equal	 			不等于
$\parallel$ 	parallel 					平行
$\perp$			perpendicular to 			垂直
$\angle$		angle 						角度
$\triangle$ 	triangle 					三角形
$\square$ 		square 						正方形
$\sim$			similar 					相似
$\exists$		there exists 				存在
$\forall$		for all 					任意
$\subset$		is proper subset of 		真子集
$\subseteq$		is subset of 				子集
$\varnothing$	empty set 					空集
$\supset$		is proper superset of 		真超集
$\supseteq$		is superset of 				超集
$\cap$			intersection 				交集
$\cup$			union 						并集
$\in$			is member of 				属于
$\notin$		is not member of 			不属于
$\N$ 			set of natural numbers 		自然数集合
$\Z$ 			set of integers 			整数集合
$\rightarrow$	arrow to the right 			向右箭头
$\leftarrow$	arrow to the left 			向左箭头
$\mapsto$ 		maps to 					映射
$\implies$		implies 					推出
$\uparrow$		upward arrow 				向上箭头
$\Uparrow$		upward arrow 				向上箭头
$\downarrow$	downward arrow				向下箭头
$\Downarrow$	downward arrow				向下箭头
$\therefore$	therefore sign 				所以
$\because$ 		because sign 				因为
$\star$ 		asterisk, star, pointer 	星号
$!$ 			exclamation mark			叹号,阶乘
$| x |$			x absolute value of x 		绝对值
$\lfloor x \rfloor$		the floor of x 		向下取整
$\lceil x \rceil$		the ceiling of x 	向上取整
$x!$			x factorial 				阶乘

相关样式展示

  1. \(\times\)
  2. \(\div\) 除以
  3. \(\otimes\) 张量积
  4. \((\) 左圆括号
  5. \()\) 右圆括号
  6. \([\) 左方括号
  7. \(]\) 右方括号
  8. \(\{\) 左大括号
  9. \(\}\) 右大括号
  10. \(\pm\) 正负号
  11. \(\mp\) 负正号
  12. \(<\) 小于
  13. \(\leq\) 小于等于
  14. \(\ll\) 远小于
  15. \(>\) 大于号
  16. \(\geq\) 大于等于
  17. \(\gg\) 远大于
  18. \(=\) 等于
  19. \(\equiv\) 完全相等
  20. \(\approx\) 约等于
  21. \(\propto\) 正比于
  22. \(\partial\) 偏导
  23. \(\nabla\) 梯度算子
  24. \(\infty\) 无穷
  25. \(\neq\) 不等于
  26. \(\parallel\) 平行
  27. \(\perp\) 垂直
  28. \(\angle\) 角度
  29. \(\triangle\) 三角形
  30. \(\square\) 正方形
  31. \(\sim\) 相似
  32. \(\exists\) 存在
  33. \(\forall\) 任意
  34. \(\subset\) 真子集
  35. \(\subseteq\) 子集
  36. \(\varnothing\) 空集
  37. \(\supset\) 真超集
  38. \(\supseteq\) 超集
  39. \(\cap\) 交集
  40. \(\cup\) 并集
  41. \(\in\) 属于
  42. \(\notin\) 不属于
  43. \(\N\) 自然数集合
  44. \(\Z\) 整数集合
  45. \(\rightarrow\) 向右箭头
  46. \(\leftarrow\) 向左箭头
  47. \(\mapsto\) 映射
  48. \(\implies\) 推出
  49. \(\uparrow\) 向上箭头
  50. \(\Uparrow\) 向上箭头
  51. \(\downarrow\) 向下箭头
  52. \(\Downarrow\) 向下箭头
  53. \(\therefore\) 所以
  54. \(\because\) 因为
  55. \(\star\) 星号
  56. \(!\) 叹号,阶乘
  57. \(| x |\) 绝对值
  58. \(\lfloor x \rfloor\) 向下取整
  59. \(\lceil x \rceil\) 向上取整
  60. \(x!\) 阶乘

2.用 LaTex 写公式

2.1 多项式的数学表达

LaTex
$x^{2}-y^{2} = \left(x+y\right)\left(x-y\right)$			
$a_{n}x^{n} + a_{n-1}x^{n-1} + \dotsb + a_{2}x^{2} + a_{1}x + a_{0}$
$\sum_{k=0}^{n}a_{k}x^{k}$
$ ax^{2} + bx + c = 0\ (a\neq 0) $

相关样式展示

  1. \(x^{2}-y^{2} = \left(x+y\right)\left(x-y\right)\)
  2. \(a_{n}x^{n} + a_{n-1}x^{n-1} + \dotsb + a_{2}x^{2} + a_{1}x + a_{0}\)
  3. \(\sum_{k=0}^{n}a_{k}x^{k}\)
  4. $ ax^{2} + bx + c = 0\ (a\neq 0) $

2.2 根式的数学表达

LaTex
${\sqrt[{n}]{a^{m}}}=(a^{m})^{1/n}=a^{m/n}=(a^{1/n})^{m}=({\sqrt[ {n}]{a}})^{m}$
$\left({\sqrt {1-x^{2}}}\right)^{2}$

相关样式展示

  1. \({\sqrt[{n}]{a^{m}}}=(a^{m})^{1/n}=a^{m/n}=(a^{1/n})^{m}=({\sqrt[ {n}]{a}})^{m}\)

  2. \(\left({\sqrt {1-x^{2}}}\right)^{2}\)

2.3 分式的数学表达

Latex
$\frac {1}{x+1} + {\frac {1}{x-1}} = {\frac {2x}{x^{2} - 1}}$
$x_{1, 2} = {\frac {-b\pm {\sqrt {b^{2} - 4ac}}}{2a}}$

相关样式展示

  1. \(\frac {1}{x+1} + {\frac {1}{x-1}} = {\frac {2x}{x^{2} - 1}}\)

  2. \(x_{1, 2} = {\frac {-b\pm {\sqrt {b^{2} - 4ac}}}{2a}}\)

2.4 函数的数学表达

LaTex
$f(x)=ax^{2}+bx+c~~{\text{ with }}~~a,b,c\in \mathbb {R} ,\ a\neq 0$
$f(x_1, x_2) = x_1^2 + x_2^2 + 2x_1x_2$
$\log_{b}(xy)=\log_{b}x+\log_{b}y$
$\ln(xy)=\ln x+\ln y{\text{ for }} x>0 {\text{ and }} y>0$
$f(x)=a\exp \left(-{\frac {(x-b)^{2}}{2c^{2}}}\right)$

相关样式展示

  1. \(f(x)=ax^{2}+bx+c~~{\text{ with }}~~a,b,c\in \mathbb {R} ,\ a\neq 0\)

  2. \(f(x_1, x_2) = x_1^2 + x_2^2 + 2x_1x_2\)

  3. \(\log_{b}(xy)=\log_{b}x+\log_{b}y\)

  4. \(\ln(xy)=\ln x+\ln y{\text{ for }} x>0 {\text{ and }} y>0\)

  5. \(f(x)=a\exp \left(-{\frac {(x-b)^{2}}{2c^{2}}}\right)\)

2.5 三角恒等式

LaTex
$\sin ^{2}\theta +\cos ^{2}\theta =1$
$\sin 2\theta =2\sin \theta \cos \theta$
$\sin(\alpha \pm \beta )=\sin \alpha \cos \beta \pm \cos \alpha \sin \beta$
$\tan(\alpha \pm \beta )=\frac {\tan \alpha \pm \tan \beta }{1\mp \tan \alpha \tan \beta }$

相关样式展示

  1. \(\sin ^{2}\theta +\cos ^{2}\theta =1\)

  2. \(\sin 2\theta =2\sin \theta \cos \theta\)

  3. \(\sin(\alpha \pm \beta )=\sin \alpha \cos \beta \pm \cos \alpha \sin \beta\)

  4. \(\tan(\alpha \pm \beta )=\frac {\tan \alpha \pm \tan \beta }{1\mp \tan \alpha \tan \beta }\)

2.6 微积分数学表达

LaTex
$\exp(x)=\sum _{k=0}^{\infty }{\frac {x^{k}}{k!}}=1+x+{\frac {x^{2}}{2}}+{\frac {x^{3}}{6}}+{\frac {x^{4}}{24}}+\cdots $
$ \left(\sum _{i=0}^{n}a_{i}\right)\left(\sum _{j=0}^{n}b_{j}\right)=\sum _{i=0}^{n}\sum _{j=0}^{n}a_{i}b_{j}$
$\exp(x) =\lim _{n\to \infty }\left(1+{\frac {x}{n}}\right)^{n}$
$\frac {\mathrm{d}}{\mathrm{d}x} \exp(f(x)) =f'(x) \exp(f(x))$
$\int_{a}^{b}f(x) \mathrm {d} x$
$\int _{-\infty }^{\infty }\exp(- x^{2})\mathrm{d}x={\sqrt {\mathrm{\pi} }}$
$\int _{-\infty }^{\infty }\int _{- \infty }^{\infty } \exp \left({- \left(x^{2}+y^{2}\right)} \right) {\mathrm{d}x} {\mathrm{d}y} = \pi$
$\frac {\partial ^{2}f}{\partial x^{2}}=f''_{xx}=\partial _{xx}f=\partial _{x}^{2}f$
${\frac {\partial ^{2}f}{\partial y \partial x}}={\frac {\partial }{\partial y}}\left({\frac {\partial f}{\partial x}}\right)=f''_{xy}$

相关样式展示

  1. $\exp(x)=\sum _{k=0}^{\infty }{\frac {x^{k}}{k!}}=1+x+{\frac {x^{2}}{2}}+{\frac {x^{3}}{6}}+{\frac {x^{4}}{24}}+\cdots $
  2. $ \left(\sum {i=0}^{n}a\right)\left(\sum {j=0}^{n}b\right)=\sum {i=0}^{n}\sum {j=0}^{n}ab$
  3. \(\exp(x) =\lim _{n\to \infty }\left(1+{\frac {x}{n}}\right)^{n}\)
  4. \(\frac {\mathrm{d}}{\mathrm{d}x} \exp(f(x)) =f'(x) \exp(f(x))\)
  5. \(\int_{a}^{b}f(x) \mathrm {d} x\)
  6. \(\int _{-\infty }^{\infty }\exp(- x^{2})\mathrm{d}x={\sqrt {\mathrm{\pi} }}\)
  7. \(\int _{-\infty }^{\infty }\int _{- \infty }^{\infty } \exp \left({- \left(x^{2}+y^{2}\right)} \right) {\mathrm{d}x} {\mathrm{d}y} = \pi\)
  8. \(\frac {\partial ^{2}f}{\partial x^{2}}=f''_{xx}=\partial _{xx}f=\partial _{x}^{2}f\)
  9. \({\frac {\partial ^{2}f}{\partial y \partial x}}={\frac {\partial }{\partial y}}\left({\frac {\partial f}{\partial x}}\right)=f''_{xy}\)

2.7 向量的表达

LaTex
$\mathbf {a} = {\begin{bmatrix} a_{1} \\ a_{2} \\ a_{3} \end{bmatrix}} = [a_{1}\ a_{2}\ a_{3}]^{\operatorname {T} }$
$\left\|\mathbf {a} \right\|=\sqrt {a_{1}^{2}+a_{2}^{2}+a_{3}^{2}}$
$\mathbf {a} \cdot \mathbf {b} = a_{1}b_{1} + a_{2}b_{2} + a_{3}b_{3}$ 
$\mathbf {a} \cdot \mathbf {b} =\left\|\mathbf {a} \right\|\left\|\mathbf {b} \right\|\cos \theta $

相关样式展示

  1. \(\mathbf {a} = {\begin{bmatrix} a_{1} \\ a_{2} \\ a_{3} \end{bmatrix}} = [a_{1}\ a_{2}\ a_{3}]^{\operatorname {T} }\)

  2. \(\left\|\mathbf {a} \right\|=\sqrt {a_{1}^{2}+a_{2}^{2}+a_{3}^{2}}\)

  3. \(\mathbf {a} \cdot \mathbf {b} = a_{1}b_{1} + a_{2}b_{2} + a_{3}b_{3}\)

  4. $\mathbf {a} \cdot \mathbf {b} =\left|\mathbf {a} \right|\left|\mathbf {b} \right|\cos \theta $

  5. \(\|\mathbf {x} \|_{p}=\left(\sum _{i=1}^{n}\left|x_{i}\right|^{p}\right)^{1/p}\)

2.8 矩阵的表达

LaTex
$\mathbf {A} = {\begin{bmatrix} 1 & 2\\ 3 & 4 \\ 5 & 6 \end{bmatrix}}$
$\mathbf {A} ={\begin{bmatrix}a_{11}&a_{12}&\cdots &a_{1n}\\a_{21}&a_{22}&\cdots &a_{2n}\\\vdots &\vdots &\ddots &\vdots \\a_{m1}&a_{m2}&\cdots &a_{mn}\end{bmatrix}}$
$\left(\mathbf {A} +\mathbf {B} \right)^{\operatorname {T} }=\mathbf {A} ^{\operatorname {T} }+\mathbf {B} ^{\operatorname {T} }$
$\left(\mathbf {AB} \right)^{\operatorname {T} }=\mathbf {B} ^{\operatorname {T} }\mathbf {A} ^{\operatorname {T} }$
$ \left(\mathbf {A} ^{\operatorname {T} }\right)^{-1}=\left(\mathbf {A} ^{- 1}\right)^{\operatorname {T} }$
$\mathbf {u} \otimes \mathbf {v} = \mathbf {u} \mathbf {v} ^ {\operatorname {T}} = {\begin{bmatrix}u_{1} \\ u_{2} \\ u_{3} \\ u_{4} \end{bmatrix}} {\begin{bmatrix} v_{1}&v_{2}&v_{3} \end{bmatrix}} = {\begin{bmatrix} u_{1}v_{1} & u_{1}v_{2} & u_{1}v_{3} \\ u_{2}v_{1} & u_{2}v_{2} & u_{2}v_{3} \\ u_{3}v_{1} & u_{3}v_{2} & u_{3}v_{3} \\ u_{4}v_{1} & u_{4}v_{2} & u_{4}v_{3} \end{bmatrix}}$
$\det {\begin{bmatrix} a & b \\ c & d \end{bmatrix}} = ad-bc$

相关样式展示

  1. \(\mathbf {A} = {\begin{bmatrix} 1 & 2\\ 3 & 4 \\ 5 & 6 \end{bmatrix}}\)
  2. \(\mathbf {A} ={\begin{bmatrix}a_{11}&a_{12}&\cdots &a_{1n}\\a_{21}&a_{22}&\cdots &a_{2n}\\\vdots &\vdots &\ddots &\vdots \\a_{m1}&a_{m2}&\cdots &a_{mn}\end{bmatrix}}\)
  3. \(\left(\mathbf {A} +\mathbf {B} \right)^{\operatorname {T} }=\mathbf {A} ^{\operatorname {T} }+\mathbf {B} ^{\operatorname {T} }\)
  4. \(\left(\mathbf {AB} \right)^{\operatorname {T} }=\mathbf {B} ^{\operatorname {T} }\mathbf {A} ^{\operatorname {T} }\)
  5. $ \left(\mathbf {A} ^{\operatorname {T} }\right)^{-1}=\left(\mathbf {A} ^{- 1}\right)^{\operatorname {T} }$
  6. \(\mathbf {u} \otimes \mathbf {v} = \mathbf {u} \mathbf {v} ^ {\operatorname {T}} = {\begin{bmatrix}u_{1} \\ u_{2} \\ u_{3} \\ u_{4} \end{bmatrix}} {\begin{bmatrix} v_{1}&v_{2}&v_{3} \end{bmatrix}} = {\begin{bmatrix} u_{1}v_{1} & u_{1}v_{2} & u_{1}v_{3} \\ u_{2}v_{1} & u_{2}v_{2} & u_{2}v_{3} \\ u_{3}v_{1} & u_{3}v_{2} & u_{3}v_{3} \\ u_{4}v_{1} & u_{4}v_{2} & u_{4}v_{3} \end{bmatrix}}\)
  7. \(\det {\begin{bmatrix} a & b \\ c & d \end{bmatrix}} = ad-bc\)

2.9 概率统计的表达

LaTex
$\Pr(A\vert B)={\frac {\Pr(B\vert A)\Pr(A)}{\Pr(B)}}$
$ f_{X\vert Y=y}(x)={\frac {f_{X,Y}(x,y)}{f_{Y}(y)}}$
$\operatorname {var} (X) = \operatorname {E} \left[X^{2}\right]-\operatorname {E} [X]^{2}$
$\operatorname {var} (aX+bY)=a^{2}\operatorname {var} (X) + b^{2}\operatorname {var} (Y) + 2ab \operatorname {cov} (X,Y)$
$\operatorname {E} [X]=\int _{- \infty }^{\infty }xf_{X}(x) \operatorname {d}x$
$ X\sim N(\mu ,\sigma ^{2})$
$\frac {\exp \left(-{\frac {1}{2}}\left({\mathbf {x} }-{\boldsymbol {\mu }}\right)^{\mathrm {T} }{\boldsymbol {\Sigma }}^{-1}\left({\mathbf {x} }- {\boldsymbol {\mu }}\right)\right)}{\sqrt {(2\pi )^{k}|{\boldsymbol {\Sigma }}|}}$

相关样式展示

  1. \(\Pr(A\vert B)={\frac {\Pr(B\vert A)\Pr(A)}{\Pr(B)}}\)
  2. $ f_{X\vert Y=y}(x)={\frac {f_{X,Y}(x,y)}{f_{Y}(y)}}$
  3. \(\operatorname {var} (X) = \operatorname {E} \left[X^{2}\right]-\operatorname {E} [X]^{2}\)
  4. \(\operatorname {var} (aX+bY)=a^{2}\operatorname {var} (X) + b^{2}\operatorname {var} (Y) + 2ab \operatorname {cov} (X,Y)\)
  5. \(\operatorname {E} [X]=\int _{- \infty }^{\infty }xf_{X}(x) \operatorname {d}x\)
  6. $ X\sim N(\mu ,\sigma ^{2})$
  7. \(\frac {\exp \left(-{\frac {1}{2}}\left({\mathbf {x} }-{\boldsymbol {\mu }}\right)^{\mathrm {T} }{\boldsymbol {\Sigma }}^{-1}\left({\mathbf {x} }- {\boldsymbol {\mu }}\right)\right)}{\sqrt {(2\pi )^{k}|{\boldsymbol {\Sigma }}|}}\)
posted @ 2025-06-26 13:17  小西贝の博客  阅读(123)  评论(0)    收藏  举报