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由于公式太多,汇总成一篇容易打不开,所以分三篇。整篇链接:https://blog.csdn.net/zhaohongfei_358/article/details/106039576 章节链接基础回顾篇https://blog.csdn.net/zhaohongfei_358/article/details/119929920高等数学篇https://blog.csdn.net/zhaohongfei_358/article/details/119929988线性代数篇https://blog.csdn.net/zhaohongfei_358/article/details/119930063 文章目录 极限相关公式数列极限递推式重要极限公式常用等价无穷小1^∞ 型 导数相关公式导数定义微分定义连续,可导及可微关系一元函数多元函数 导数四则运算复合函数求导反函数求导参数方程求导变限积分求导公式基本初等函数的导数公式(❤❤❤)高阶导数的运算常用初等函数的n阶导数公式极值判别条件凹凸性判定拐点判别条件斜渐近线曲率 积分相关公式定积分的精确定义分布积分公式分部积分表格法区间再现公式华里士公式敛散性判别公式基本积分公式重要积分公式 有理函数的拆分积分求平均值定积分应用定积分求平面图形面积定积分求旋转体的体积平面曲线的弧长旋转曲面的面积平面截面面积为已知的立体体积变力沿直线做功抽水做功水压力质心直线段的质心(一维)不均匀薄片质心(二维) 形心质量转动惯量物理公式 泰勒公式拉格朗日余项的泰勒公式佩亚诺余项的泰勒公式常用的泰勒展开式 中值定理罗尔定理罗尔定理推论罗尔定理证明题辅助函数构造微分方程构造罗尔定理辅助函数拉格朗日中值定理柯西中值定理积分中值定理 多元微积分相关公式多元微分定义多元隐函数求导极坐标下二重积分计算法隐函数存在定理多元函数极值判定拉格朗日数乘法求最值多重积分的应用空间曲面的面积 微分方程一阶线性微分方程二阶常系数齐次线性微分方程的通解三阶常系数齐次线性微分方程的通解二阶常系数非齐次线性微分方程的特解“算子法”求二阶常系数非齐次线性微分方程的特解 极限相关公式 数列极限递推式a n + 1 = f ( a n ) 结 论 一 : f ′ ( x ) > 0 , { a 2 > a 1 ⟹ { a n } ↗ 单 调 递 增 a 2 < a 1 ⟹ { a n } ↘ 单 调 递 减 结 论 二 ( 压 缩 映 像 原 理 ) : ∃ k ∈ ( 0 , 1 ) , 使 得 ∣ f ′ ( x ) ∣ ≤ k ⟹ a n 收 敛 \begin{aligned} & a_{n+1} = f(a_n) \\\\ 结论一: & f'(x) > 0 , \begin{cases} a_2 > a_1 \implies \{ a_n \} \nearrow单调递增 \\ a_2 < a_1 \implies \{ a_n \} \searrow单调递减 \end{cases} \\\\ 结论二(压缩映像原理):& \exist k \in (0,1),使得 |f'(x)| \le k \implies {a_n} 收敛 \end{aligned} 结论一:结论二(压缩映像原理):an+1=f(an)f′(x)>0,{a2>a1⟹{an}↗单调递增a2f[g(x)]}′=f′[g(x)]g′(x) 反函数求导y = f ( x ) , x = φ ( y ) ⟹ φ ′ ( y ) = 1 f ′ ( x ) y x ′ = d y d x = 1 d x d y = 1 x y ′ y x x ′ ′ = d 2 y d x 2 = d ( d y d x ) d x = d ( 1 x y ′ ) d x = d ( 1 x y ′ ) d y ⋅ d y d x = d ( 1 x y ′ ) d y ⋅ 1 x y ′ = − x y y ′ ′ ( x y ′ ) 3 \begin{aligned} & y = f(x), x = \varphi(y) \implies \varphi ' (y) = \frac{1}{f'(x)} \\ \\ & y'_x = \frac{dy}{dx} = \frac{1}{\frac{dx}{dy}} = \frac{1}{x'_y} \\ \\ & y^{''}_{xx} = \frac{d^2 y}{dx^2} = \frac{d(\frac{dy}{dx})}{dx} = \frac{d(\frac{1}{x'_y})}{dx} = \frac{d(\frac{1}{x'_y})}{dy} \cdot \frac{dy}{dx} = \frac{d(\frac{1}{x'_y})}{dy} \cdot \frac{1}{x'_y} = \frac{-x^{''}_{yy}}{(x'_y)^3} \end{aligned} y=f(x),x=φ(y)⟹φ′(y)=f′(x)1yx′=dxdy=dydx1=xy′1yxx′′=dx2d2y=dxd(dxdy)=dxd(xy′1)=dyd(xy′1)⋅dxdy=dyd(xy′1)⋅xy′1=(xy′)3−xyy′′ 参数方程求导{ x = φ ( t ) y = ψ ( t ) d y d x = d y / d t d x / d t = ψ ′ ( t ) φ ′ ( t ) d 2 y d x 2 = d ( d y d x ) d x = d ( d y d x ) / d t d x / d t = ψ ′ ′ ( t ) φ ′ ( t ) − ψ ′ ( t ) φ ′ ′ ( t ) [ φ ′ ( t ) ] 3 \begin{aligned} & \begin{cases} x = \varphi (t) \\ y = \psi (t) \end{cases} \\\\ & \frac{dy}{dx} = \frac{dy/dt}{dx/dt} = \frac{\psi ' (t)}{\varphi ' (t)} \\ \\ & \frac{d^2 y}{dx^2} = \frac{d(\frac{dy}{dx})}{dx} = \frac {d(\frac{dy}{dx})/dt}{dx/dt} = \frac{\psi '' (t) \varphi '(t) - \psi '(t) \varphi '' (t) }{[\varphi ' (t)]^3} \end{aligned} {x=φ(t)y=ψ(t)dxdy=dx/dtdy/dt=φ′(t)ψ′(t)dx2d2y=dxd(dxdy)=dx/dtd(dxdy)/dt=[φ′(t)]3ψ′′(t)φ′(t)−ψ′(t)φ′′(t) 变限积分求导公式设 F ( x ) = ∫ φ 1 ( x ) φ 2 ( x ) f ( t ) d t , 则 F ′ ( x ) = d d x [ ∫ φ 1 ( x ) φ 2 ( x ) f ( t ) d t ] = f [ φ 2 ( x ) ] φ 2 ′ ( x ) − f [ φ 1 ( x ) ] φ 1 ′ ( x ) \begin{aligned} & 设 F(x) = \int ^{\varphi_2(x)}_{\varphi_1(x)} f(t) dt, 则 \\ \\ & F'(x) = \frac{d}{dx}\begin{bmatrix}\int ^{\varphi_2(x)}_{\varphi_1(x)} f(t) dt \end{bmatrix} = f[\varphi _2(x)]\varphi '_2(x) - f[\varphi_1(x)]\varphi '_1(x) \end{aligned} 设F(x)=∫φ1(x)φ2(x)f(t)dt,则F′(x)=dxd[∫φ1(x)φ2(x)f(t)dt]=f[φ2(x)]φ2′(x)−f[φ1(x)]φ1′(x) 基本初等函数的导数公式(❤❤❤)( x a ) ′ = a x a − 1 ( a 为 常 数 ) ( a x ) ′ = a x ln a ( e x ) ′ = e x ( l o g a x ) ′ = 1 x ln a ( a > 0 , a ≠ 1 ) ( ln x ) ′ = 1 x ( sin x ) ′ = cos x ( cos x ) ′ = − sin x ( arcsin x ) ′ = 1 1 − x 2 ( arccos x ) ′ = − 1 1 − x 2 ( tan x ) ′ = sec 2 x ( cot x ) ′ = − csc 2 x ( arctan x ) ′ = 1 1 + x 2 ( a r c c o t x ) ′ = − 1 1 + x 2 ( sec x ) ′ = sec x ⋅ tan x ( csc x ) ′ = − csc x ⋅ cot x [ ln ( x + x 2 + 1 ) ] ′ = 1 x 2 + 1 [ ln ( x + x 2 − 1 ) ] ′ = 1 x 2 − 1 \begin{aligned} & (x^a)' = a x^{a-1} ~~~~~(a为常数) \\ \\ & (a^x)' = a^x \ln a \\ \\ & (e^x)' = e^x \\ \\ & (log_a x)' = \frac{1}{x \ln a} ~~~~~(a>0, a \ne 1) \\ \\ & (\ln x)' = \frac{1}{x} \\ \\ & (\sin x)' = \cos x \\ \\ & (\cos x)' = -\sin x \\ \\ & (\arcsin x)' = \frac{1}{\sqrt{1-x^2}} \\ \\ & (\arccos x)' = - \frac{1}{\sqrt{1-x^2}} \\ \\ & (\tan x)' = \sec ^2 x \\ \\ & (\cot x)' = - \csc^2 x \\ \\ & (\arctan x)' = \frac{1}{1+x^2} \\ \\ & (arccot ~ x)' = - \frac{1}{1+x^2} \\ \\ & (\sec x)' = \sec x \cdot \tan x \\ \\ & (\csc x)' = - \csc x \cdot \cot x \\ \\ & [\ln (x+\sqrt{x^2+1})]' = \frac{1}{\sqrt{x^2+1}} \\ \\ & [\ln (x+\sqrt{x^2-1})]' = \frac{1}{\sqrt{x^2-1}} \\ \\ \end{aligned} (xa)′=axa−1 (a为常数)(ax)′=axlna(ex)′=ex(logax)′=xlna1 (a>0,a=1)(lnx)′=x1(sinx)′=cosx(cosx)′=−sinx(arcsinx)′=1−x2 1(arccosx)′=−1−x2 1(tanx)′=sec2x(cotx)′=−csc2x(arctanx)′=1+x21(arccot x)′=−1+x21(secx)′=secx⋅tanx(cscx)′=−cscx⋅cotx[ln(x+x2+1 )]′=x2+1 1[ln(x+x2−1 )]′=x2−1 1 高阶导数的运算[ u ± v ] ( n ) = u ( n ) ± v ( n ) [u \pm v ]^{(n)} = u^{(n)} \pm v^{(n)} [u±v](n)=u(n)±v(n) ( u v ) ( n ) = u ( n ) v + C n 1 u ( n − 1 ) v ′ + C n 2 u ( n − 2 ) v ′ ′ + . . . + C n k u ( n − k ) v ( k ) + . . . + C n n − 1 u ′ v ( n − 1 ) + u v ( n ) = ∑ k = 0 n C n k u ( n − k ) v ( k ) \begin{aligned} (uv)^{(n)} & = u^{(n)}v + C_n^1 u^{(n-1)}v' + C_n^2 u^{(n-2)}v'' + ... + C_n^k u^{(n-k)}v^{(k)} + ... + C_n^{n-1} u'v^{(n-1)} + uv^{(n)} \\ & = \displaystyle\sum_{k=0}^n C_n^k u^{(n-k)}v^{(k)} \end{aligned} (uv)(n)=u(n)v+Cn1u(n−1)v′+Cn2u(n−2)v′′+...+Cnku(n−k)v(k)+...+Cnn−1u′v(n−1)+uv(n)=k=0∑nCnku(n−k)v(k) 常用初等函数的n阶导数公式( a x ) ( n ) = a x ( ln a ) n ( e x ) ( n ) = e x ( sin k x ) ( n ) = k n sin ( k x + n ⋅ π 2 ) ( cos k x ) ( n ) = k n cos ( k x + n ⋅ π 2 ) ( ln x ) ( n ) = ( − 1 ) n − 1 ( n − 1 ) ! x n ( x > 0 ) [ ln ( 1 + x ) ] ( n ) = ( − 1 ) n − 1 ( n − 1 ) ! ( x + 1 ) n ( x > − 1 ) [ ( x + x 0 ) m ] ( n ) = m ( m − 1 ) ( m − 2 ) ⋅ ⋅ ⋅ ⋅ ( m − n + 1 ) ( x + x 0 ) m − n ( 1 x + a ) ( n ) = ( − 1 ) n ⋅ n ! ( x + a ) n + 1 \begin{aligned} & (a^x)^{(n)} = a^x (\ln a)^n \\ \\ & (e^x)^{(n)} = e^x \\ \\ & (\sin kx)^{(n)} = k^n \sin (kx + n\cdot \frac{\pi}{2}) \\ \\ & (\cos kx)^{(n)} = k^n \cos (kx + n\cdot \frac{\pi}{2}) \\ \\ & (\ln x) ^ {(n)} = (-1)^{n-1} \frac{(n-1)!}{x^n} ~~~~~(x>0) \\ \\ & [\ln(1+x)]^{(n)} = (-1)^{n-1} \frac{(n-1)!}{(x+1)^n} ~~~~~(x>-1) \\ \\ & [(x+x_0)^m]^{(n)} = m(m-1)(m-2)\cdotp\cdotp\cdotp\cdot (m-n+1)(x+x_0)^{m-n} \\ \\ & (\frac{1}{x+a})^{(n)} = \frac{(-1)^n \cdot n!}{(x+a)^{n+1}} \\ \\ \end{aligned} (ax)(n)=ax(lna)n(ex)(n)=ex(sinkx)(n)=knsin(kx+n⋅2π)(coskx)(n)=kncos(kx+n⋅2π)(lnx)(n)=(−1)n−1xn(n−1)! (x>0)[ln(1+x)](n)=(−1)n−1(x+1)n(n−1)! (x>−1)[(x+x0)m](n)=m(m−1)(m−2)⋅⋅⋅⋅(m−n+1)(x+x0)m−n(x+a1)(n)=(x+a)n+1(−1)n⋅n! 极值判别条件{ 1. f ′ ( x ) 左 右 异 号 ⟹ { 左 正 右 负 ⟹ 极 大 值 左 负 右 正 ⟹ 极 小 值 2. f ′ ( x ) = 0 , f ′ ′ ( x ) ≠ 0 ⟹ { f ′ ′ ( x ) < 0 ⟹ 极 大 值 f ′ ′ ( x ) > 0 ⟹ 极 小 值 3. f ′ ′ ( x ) 到 f ( n − 1 ) ( x ) = 0 , f ( n ) ( x ) ≠ 0 , n 为 偶 数 ⟹ { f ( n ) ( x ) < 0 ⟹ 极 大 值 f ( n ) ( x ) > 0 ⟹ 极 小 值 \begin{cases} 1.~~f'(x)左右异号 \implies \begin{cases} 左正右负 \implies 极大值 \\ 左负右正 \implies 极小值 \end{cases} \\ \\ 2.~~f'(x)=0, f''(x)\ne 0 \implies \begin{cases} f''(x) < 0 \implies 极大值 \\ f''(x)>0 \implies 极小值 \end{cases} \\ \\ 3. ~~f''(x) 到 f^{(n-1)}(x)=0 ,f^{(n)}(x) \ne 0, n为偶数 \implies \begin{cases} f^{(n)}(x) < 0 \implies 极大值 \\ f^{(n)}(x) > 0 \implies 极小值 \end{cases} \end{cases} ⎩⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎧1. f′(x)左右异号⟹{左正右负⟹极大值左负右正⟹极小值2. f′(x)=0,f′′(x)=0⟹{f′′(x)0⟹极小值3. f′′(x)到f(n−1)(x)=0,f(n)(x)=0,n为偶数⟹{f(n)(x)0⟹极小值 凹凸性判定1. { f ( x 1 + x 2 2 ) < f ( x 1 ) + f ( x 2 ) 2 ⟹ 凹 f ( x 1 + x 2 2 ) > f ( x 1 ) + f ( x 2 ) 2 ⟹ 凸 2. { f ′ ′ ( x ) > 0 ⟹ 凹 f ′ ′ ( x ) < 0 ⟹ 凸 \begin{aligned} 1.&\begin{cases} f(\frac{x_1+x_2}{2}) < \frac{f(x_1)+f(x_2)}{2} \implies 凹 \\\\ f(\frac{x_1+x_2}{2}) > \frac{f(x_1)+f(x_2)}{2} \implies 凸 \end{cases} \\\\ 2.&\begin{cases} f''(x) > 0 \implies 凹 \\\\ f''(x) < 0 \implies 凸 \end{cases} \end{aligned} 1.2.⎩⎪⎨⎪⎧f(2x1+x2)2f(x1)+f(x2)⟹凸⎩⎪⎨⎪⎧f′′(x)>0⟹凹f′′(x) 0 ⟹ 凸 → 凹 3. f ′ ′ ( x ) 到 f ( n − 1 ) ( x ) = 0 , f ( n ) ( x ) ≠ 0 , n 为 奇 数 ⟹ { f ( n ) ( x ) < 0 ⟹ 凹 → 凸 f ( n ) ( x ) > 0 ⟹ 凸 → 凹 \begin{cases} 1.~~f''(x)左右异号 \implies \begin{cases} 左负右正 \implies 凸 \to 凹 \\ 左正右负 \implies 凹 \to 凸 \end{cases} \\ \\ 2.~~f''(x)=0, f'''(x)\ne 0 \implies \begin{cases} f'''(x) < 0 \implies 凹 \to 凸 \\ f'''(x)>0 \implies 凸 \to 凹 \end{cases} \\ \\ 3. ~~f''(x) 到 f^{(n-1)}(x)=0 ,f^{(n)}(x) \ne 0, n为奇数 \implies \begin{cases} f^{(n)}(x) < 0 \implies 凹 \to 凸 \\ f^{(n)}(x) > 0 \implies 凸 \to 凹 \end{cases} \end{cases} ⎩⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎧1. f′′(x)左右异号⟹{左负右正⟹凸→凹左正右负⟹凹→凸2. f′′(x)=0,f′′′(x)=0⟹{f′′′(x)0⟹凸→凹3. f′′(x)到f(n−1)(x)=0,f(n)(x)=0,n为奇数⟹{f(n)(x)0⟹凸→凹 斜渐近线lim x → + ∞ f ( x ) x = a lim x → + ∞ ( f ( x ) − a x ) = b ⟹ 斜 渐 近 线 为 : y = a x + b \lim_{x \to +\infty} \frac{f(x)}{x} = a ~~~~\lim_{x \to + \infty}(f(x)-ax) = b \implies 斜渐近线为: y=ax+b x→+∞limxf(x)=a x→+∞lim(f(x)−ax)=b⟹斜渐近线为:y=ax+b 曲率密 切 圆 半 径 r = ( 1 + y ′ 2 ) 3 2 ∣ y ′ ′ ∣ 曲 率 K = 1 r = ∣ y ′ ′ ∣ ( 1 + y ′ 2 ) 3 2 曲 率 圆 ( X − ( x − y ′ ( 1 + y ′ 2 ) y ′ ′ 2 ) ) 2 + ( Y − ( y + 1 + y ′ 2 y ′ ′ 2 ) ) = ( ( 1 + y ′ 2 ) 3 2 ∣ y ′ ′ ∣ ) 2 \begin{aligned} 密切圆半径 ~~~~~ & r = \frac{(1+y'^2)^{\frac{3}{2}}}{|y''|} \\ \\ 曲率 ~~~~~ &K = \frac{1}{r} = \frac{|y''|}{(1+y'^2)^{\frac{3}{2}}} \\ \\ 曲率圆 ~~~~~& (X-(x-\frac{y'(1+y'^2)}{y''^2}))^2 +(Y-(y+\frac{1+y'^2}{y''^2})) = (\frac{(1+y'^2)^{\frac{3}{2}}}{|y''|})^2 \end{aligned} 密切圆半径 曲率 曲率圆 r=∣y′′∣(1+y′2)23K=r1=(1+y′2)23∣y′′∣(X−(x−y′′2y′(1+y′2)))2+(Y−(y+y′′21+y′2))=(∣y′′∣(1+y′2)23)2 积分相关公式 定积分的精确定义∫ a b f ( x ) d x = lim n → ∞ ∑ i = 1 n f ( a + b − a n i ) b − a n 常 用 : ∫ 0 1 f ( x ) d x = lim n → ∞ ∑ i = 1 n f ( i n ) ⋅ 1 n ∫ 0 k f ( x ) d x = lim n → ∞ ∑ i = 1 k n f ( i n ) ⋅ 1 n 二 重 定 积 分 精 确 定 义 : ∬ D f ( x , y ) d σ = lim n → ∞ ∑ i = 1 n ∑ j = 1 n f ( a + b − a n i , c + d − c n j ) ⋅ b − a n ⋅ d − c n 常 用 : ∫ 0 1 ∫ 0 1 f ( x , y ) d x d y = lim n → ∞ ∑ i = 1 n ∑ j = 1 n f ( i n , j n ) ⋅ 1 n 2 \begin{aligned} & \int_a^b f(x) dx = \lim_{n \to \infty} \displaystyle\sum_{i=1}^n f(a+\frac{b-a}{n}i)\frac{b-a}{n} \\ \\ \\ 常用:& \int_0^1 f(x) dx = \lim_{n \to \infty} \displaystyle\sum_{i=1}^n f(\frac{i}{n})\cdot\frac{1}{n} \\ \\ & \int_0^k f(x) dx = \lim_{n \to \infty} \displaystyle\sum_{i=1}^{kn} f(\frac{i}{n})\cdot\frac{1}{n} \\ \\ \\ 二重定积分精确定义:& \iint\limits_D f(x,y) d\sigma = \lim_{n \to \infty} \displaystyle\sum_{i=1}^n \displaystyle\sum_{j=1}^n f(a+\frac{b-a}{n}i, c+\frac{d-c}{n}j) \cdot \frac{b-a}{n} \cdot \frac{d-c}{n} \\ \\ \\ 常用:&\int_0^1 \int_0^1 f(x,y) dxdy = \lim_{n \to \infty} \displaystyle\sum_{i=1}^n \displaystyle\sum_{j=1}^n f(\frac{i}{n}, \frac{j}{n})\cdot \frac{1}{n^2} \end{aligned} 常用:二重定积分精确定义:常用:∫abf(x)dx=n→∞limi=1∑nf(a+nb−ai)nb−a∫01f(x)dx=n→∞limi=1∑nf(ni)⋅n1∫0kf(x)dx=n→∞limi=1∑knf(ni)⋅n1D∬f(x,y)dσ=n→∞limi=1∑nj=1∑nf(a+nb−ai,c+nd−cj)⋅nb−a⋅nd−c∫01∫01f(x,y)dxdy=n→∞limi=1∑nj=1∑nf(ni,nj)⋅n21 分布积分公式∫ u d v = u v − ∫ v d u ∫ u v ( n + 1 ) d x = u v ( n ) − u ′ v ( n − 1 ) + u ′ ′ v ( n − 2 ) − . . . + ( − 1 ) n u ( n ) v + ( − 1 ) n + 1 ∫ u ( n + 1 ) v d x \begin{aligned} & \int u dv = uv - \int vdu \\ & \int uv^{(n+1)}dx = uv^{(n)} - u'v^{(n-1)} + u''v^{(n-2)} - ... + (-1)^nu^{(n)}v + (-1)^{n+1}\int u^{(n+1)}vdx \end{aligned} ∫udv=uv−∫vdu∫uv(n+1)dx=uv(n)−u′v(n−1)+u′′v(n−2)−...+(−1)nu(n)v+(−1)n+1∫u(n+1)vdx 分部积分表格法∫ f ( x ) g ( x ) d x \int f(x) g(x) dx\\\\\\ ∫f(x)g(x)dx f ( x ) f ′ ( x ) f ′ ′ ( x ) ⋯ f ( n ) ( x ) g ( x ) g 1 ( x ) g 2 ( x ) ⋯ g n ( x ) \def\arraystretch{2} \begin{array}{c:c:c:c:c} f(x) & f'(x) & f''(x) & \cdots & f^{(n)}(x) \\ \hline g(x) & g_1(x) & g_2(x) & \cdots & g_n(x) \\ \end{array} f(x)g(x)f′(x)g1(x)f′′(x)g2(x)⋯⋯f(n)(x)gn(x) ∫ f ( x ) g ( x ) d x = f ( x ) g 1 ( x ) − f ′ ( x ) g 2 ( x ) + f ′ ′ ( x ) g 3 ( x ) − ⋯ ± ∫ f ( n ) ( x ) g n ( x ) d x 其 中 g 1 ( x ) 代 表 g ( x ) 的 积 分 , 依 次 类 推 。 公 式 为 斜 对 角 线 加 减 交 替 。 \int f(x) g(x) dx = f(x)g_1(x) - f'(x)g_2(x) + f''(x)g_3(x) - \cdots \pm \int f^{(n)}(x) g_n(x) dx \\ \\ 其中 g_1(x) 代表g(x)的积分,依次类推。公式为斜对角线加减交替。 ∫f(x)g(x)dx=f(x)g1(x)−f′(x)g2(x)+f′′(x)g3(x)−⋯±∫f(n)(x)gn(x)dx其中g1(x)代表g(x)的积分,依次类推。公式为斜对角线加减交替。 区间再现公式∫ a b f ( x ) d x = ∫ a b f ( a + b − x ) d x \int_a^b f(x) dx = \int_a^b f(a+b-x) dx ∫abf(x)dx=∫abf(a+b−x)dx 华里士公式∫ 0 π 2 sin n x d x = ∫ 0 π 2 cos n x d x = { n − 1 n ⋅ n − 3 n − 2 ⋅ ⋅ ⋅ ⋅ ⋅ 1 2 ⋅ π 2 n 为 正 偶 数 n − 1 n ⋅ n − 3 n − 2 ⋅ ⋅ ⋅ ⋅ ⋅ 2 3 n 为 大 于 1 的 奇 数 \int_0^\frac{\pi}{2} \sin ^n x dx = \int_0^\frac{\pi}{2} \cos ^n x dx = \begin{cases} \frac{n-1}{n} \cdot \frac{n-3}{n-2} \cdot\cdot\cdot\cdot\cdot \frac{1}{2} \cdot \frac{\pi}{2} ~~~~~ n 为正偶数 \\ \frac{n-1}{n} \cdot \frac{n-3}{n-2} \cdot\cdot\cdot\cdot\cdot \frac{2}{3} ~~~~~ n 为大于1的奇数 \\ \end{cases} ∫02πsinnxdx=∫02πcosnxdx={nn−1⋅n−2n−3⋅⋅⋅⋅⋅21⋅2π n为正偶数nn−1⋅n−2n−3⋅⋅⋅⋅⋅32 n为大于1的奇数 敛散性判别公式∫ 1 + ∞ 1 x p d x ⟹ { p > 1 ⟹ 收 敛 p ≤ 1 ⟹ 发 散 ∫ 0 1 1 x p d x ⟹ { p < 1 ⟹ 收 敛 p ≥ 1 ⟹ 发 散 \begin{aligned} & \int_1^{+\infty} \frac{1}{x^p} dx \implies & \begin{cases} p>1 \implies 收敛 \\ p \le 1 \implies 发散 \end{cases} \\\\ & \int_0^1 \frac{1}{x^p} dx \implies & \begin{cases} p < 1 \implies 收敛 \\ p \ge 1 \implies 发散 \end{cases} \\\\ \end{aligned} ∫1+∞xp1dx⟹∫01xp1dx⟹{p>1⟹收敛p≤1⟹发散{p 0 ∫ x α d x = 1 α + 1 x α + 1 + C ( α ≠ − 1 ) ∫ 1 x d x = ln ∣ x ∣ + C ∫ a x d x = a x ln a + C ( a > 0 , a ≠ 1 ) ∫ e x d x = e x + C ∫ sin x d x = − cos x + C ∫ cos x d x = sin x + C ∫ tan x d x = − ln ∣ cos x ∣ + C ∫ cot x d x = ln ∣ sin x ∣ + C ∫ sec x d x = ln ∣ sec x + tan x ∣ + C ∫ csc x d x = ln ∣ csc x − cot x ∣ + C ∫ sec 2 x d x = tan x + C ∫ csc 2 x d x = − cot x + C ∫ 1 a 2 + x 2 d x = 1 a arctan x a + C ∫ 1 a 2 − x 2 d x = 1 2 a ln ∣ a + x a − x ∣ + C ∫ 1 a 2 − x 2 d x = arcsin x a + C ∫ 1 x 2 ± a 2 d x = ln ∣ x + x 2 ± a 2 ∣ + C \begin{aligned} & 以下公式中,\alpha 与 a 均为常数,除声明者外,a>0 \\ \\ & \int x^\alpha dx = \frac{1}{\alpha +1} x^{\alpha + 1} + C ~~~~~(\alpha \ne -1) \\ \\ & \int \frac{1}{x} dx = \ln |x| + C \\ \\ & \int a^x dx = \frac{a^x}{\ln a} + C ~~~~~(a >0 , a\ne 1) \\ \\ & \int e^x dx = e^x + C \\ \\ & \int \sin x dx = -\cos x + C \\ \\ & \int \cos x dx = \sin x +C \\ \\ & \int \tan x dx = - \ln |\cos x| + C \\ \\ & \int \cot xdx = \ln |\sin x| + C \\ \\ & \int \sec x dx = \ln |\sec x + \tan x| + C \\ \\ & \int \csc x dx = \ln |\csc x - \cot x| + C \\ \\ & \int \sec ^2 x dx = \tan x + C \\ \\ & \int \csc^2x dx = - \cot x + C \\ \\ & \int \frac{1}{a^2 + x^2} dx = \frac{1}{a} \arctan \frac{x}{a} + C \\ \\ & \int \frac{1}{a^2-x^2} dx = \frac{1}{2a} \ln |\frac{a+x}{a-x}| + C \\ \\ & \int \frac{1}{\sqrt{a^2-x^2}} dx = \arcsin \frac{x}{a} + C \\ \\ & \int \frac{1}{\sqrt{x^2 \pm a^2}} dx = \ln |x+\sqrt{x^2 \pm a^2}| + C \end{aligned} 以下公式中,α与a均为常数,除声明者外,a>0∫xαdx=α+11xα+1+C (α=−1)∫x1dx=ln∣x∣+C∫axdx=lnaax+C (a>0,a=1)∫exdx=ex+C∫sinxdx=−cosx+C∫cosxdx=sinx+C∫tanxdx=−ln∣cosx∣+C∫cotxdx=ln∣sinx∣+C∫secxdx=ln∣secx+tanx∣+C∫cscxdx=ln∣cscx−cotx∣+C∫sec2xdx=tanx+C∫csc2xdx=−cotx+C∫a2+x21dx=a1arctanax+C∫a2−x21dx=2a1ln∣a−xa+x∣+C∫a2−x2 1dx=arcsinax+C∫x2±a2 1dx=ln∣x+x2±a2 ∣+C 重要积分公式∫ − ∞ + ∞ e − x 2 d x = 2 ∫ 0 + ∞ e − x 2 d x = π ∫ 0 + ∞ x n e − x d x = n ! ∫ − a a f ( x ) d x = ∫ 0 a [ f ( x ) + f ( − x ) ] d x ∫ 0 π x f ( sin x ) d x = π 2 ∫ 0 π f ( sin x ) d x = π ∫ 0 π 2 f ( sin x ) d x ∫ a b f ( x ) d x = ( b − a ) ∫ 0 1 f [ a + ( b − a ) x ] d x \begin{aligned} & \int_{-\infty}^{+\infty} e^{-x^2} dx = 2\int_{0}^{+\infty} e^{-x^2} dx = \sqrt{\pi} \\ \\ & \int_{0}^{+\infty} x^n e^{-x} dx = n! \\ \\ & \int_{-a}^{a} f(x) dx = \int_0^a [f(x)+f(-x)]dx \\ \\ & \int_0^\pi xf(\sin x) dx = \frac{\pi}{2} \int_0^\pi f(\sin x)dx = \pi \int_0^{\frac{\pi}{2}} f(\sin x) dx \\ \\ & \int_a^b f(x) dx = (b-a) \int_0^1 f[a+(b-a)x] dx \end{aligned} ∫−∞+∞e−x2dx=2∫0+∞e−x2dx=π ∫0+∞xne−xdx=n!∫−aaf(x)dx=∫0a[f(x)+f(−x)]dx∫0πxf(sinx)dx=2π∫0πf(sinx)dx=π∫02πf(sinx)dx∫abf(x)dx=(b−a)∫01f[a+(b−a)x]dx 有理函数的拆分P n ( x ) ( a 1 x + b 1 ) ( a 2 x + b 2 ) ( a 3 x + b 3 ) = A 1 a 1 x + b 1 + A 2 a 2 x + b 2 + A 3 a 2 x + b 2 P n ( x ) Q m ( x ) ( a x + b ) 3 = A ( x ) Q m ( x ) + A 1 ( a x + b ) 3 + A 2 ( a x + b ) 2 + A 3 ( a x + b ) P n ( x ) Q m ( x ) ( a x 2 + b x + c ) 3 = A ( x ) Q m ( x ) + A 1 x + B 1 ( a x 2 + b x + c ) 3 + A 2 x + B 2 ( a x 2 + b x + c ) 2 + A 3 x + B 3 ( a x 2 + b x + c ) \begin{aligned} & \frac{P_n(x)}{(a_1 x+b_1)(a_2 x+b_2)(a_3 x+b_3)} = \frac{A_1}{a_1 x+b_1}+\frac{A_2}{a_2 x+b_2}+\frac{A_3}{a_2 x+b_2} \\ \\ & \frac{P_n(x)}{Q_m(x)(ax+b)^3} = \frac{A(x)}{Q_m(x)} + \frac{A_1}{(ax+b)^3} + \frac{A_2}{(ax+b)^2} + \frac{A_3}{(ax+b)} \\ \\ & \frac{P_n(x)}{Q_m(x)(ax^2+bx+c)^3} = \frac{A(x)}{Q_m(x)} + \frac{A_1x+B_1}{(ax^2+bx+c)^3} + \frac{A_2x+B_2}{(ax^2+bx+c)^2} + \frac{A_3x+B_3}{(ax^2+bx+c)} \\ \\ \end{aligned} (a1x+b1)(a2x+b2)(a3x+b3)Pn(x)=a1x+b1A1+a2x+b2A2+a2x+b2A3Qm(x)(ax+b)3Pn(x)=Qm(x)A(x)+(ax+b)3A1+(ax+b)2A2+(ax+b)A3Qm(x)(ax2+bx+c)3Pn(x)=Qm(x)A(x)+(ax2+bx+c)3A1x+B1+(ax2+bx+c)2A2x+B2+(ax2+bx+c)A3x+B3 积分求平均值f ( x ) 在 [ a , b ] 上 的 平 均 值 为 : ∫ a b f ( x ) d x b − a f(x) 在[a,b]上的平均值为: \frac{\int_a^b f(x) dx}{b-a} f(x)在[a,b]上的平均值为:b−a∫abf(x)dx 定积分应用 定积分求平面图形面积y = y 1 ( x ) 与 y = y 2 ( x ) , 及 x = a , x = b ( a < b ) 所 围 成 的 平 面 图 形 面 积 : S = ∫ a b ∣ y 1 ( x ) − y 2 ( x ) ∣ d x 曲 线 r = r 1 ( θ ) 与 r = r 2 ( θ ) 与 两 射 线 θ = α 与 θ = β ( 0 < β − α ≤ 2 π ) 所 围 成 的 曲 边 扇 形 的 面 积 : S = 1 2 ∫ α β ∣ r 1 2 ( θ ) − r 2 2 ( θ ) ∣ d θ \begin{aligned} & y=y_1(x) 与 y=y_2(x),及x=a,x=b(a |
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