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Integrals

Integral expression can be added using the

\int_{lower}^{upper} 

command.

Note, that integral expression may seems a little different in inline and display math mode - in inline mode the integral symbol and the limits are compressed.

LaTeX code Output
Integral $\int_{a}^{b} x^2 dx$ inside text Example of an integral inside text
$$\int_{a}^{b} x^2 dx$$ Example of an integral

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Multiple integrals

To obtain double/triple/multiple integrals and cyclic integrals you must use amsmath and esint (for cyclic integrals) packages.

LaTeX code Output

$\iint_V \mu(u,v) \,du\,dv$$

$$\iiint_V \mu(u,v,w) \,du\,dv\,dw$$

$$\iiiint_V \mu(t,u,v,w) \,dt\,du\,dv\,dw$$

$$\idotsint_V \mu(u_1,\dots,u_k) \,du_1 \dots du_k$$

Example of multiple integrals

$$\oint_V f(s) \,ds$$

$$\oiint_V f(s,t) \,ds\,dt$$

Example of integrals

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Sums and products

Like integral, sum expression can be added using the

\sum_{lower}^{upper} 

command.

LaTeX code Output
Sum $\sum_{n=1}^{\infty} 2^{-n} = 1$ inside text Example of sum expression inside text
$$\sum_{n=1}^{\infty} 2^{-n} = 1$$ Example of sum expression

In similar way you can obtain expression with product of a sequence of factors using the

\prod_{lower}^{upper} 

command.

LaTeX code Output
Product $\prod_{i=a}^{b} f(i)$ inside text Example of limit expression inside text
$$\prod_{i=a}^{b} f(i)$$ Example of limit expression

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Limits

Limit expression can be added using the

\lim_{lower}

command.

LaTeX code Output
Limit $\lim_{x\to\infty} f(x)$ inside text Example of limits inside text
$$\lim_{x\to\infty} f(x)$$ Example of limits

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Integer and sum limits improvement

In inline math mode the integral/sum/product lower and upper limits are placed right of integral symbol. Similar is for limit expressions. If you want the limits of an integral/sum/product to be specified above and below the symbol in inline math mode, use the \limits command before limits specification.

LaTeX code Output
Integral $\int_{a}^{b} x^2 dx$ inside text Example of integral inside text
Improved integral $\int\limits_{a}^{b} x^2 dx$ inside text Example of improved integral inside text
Sum $\sum_{n=1}^{\infty} 2^{-n} = 1$ inside text Example of sum inside text
Improved sum $\sum\limits_{n=1}^{\infty} 2^{-n} = 1$ inside text Example of improved sum inside text

Moreover, adding \displaystyle beforehand will make the symbol large and easier to read.

On the other hand, \mathlarger command (provided by relsize package) is used to get bigger integral symbol in display.

$\int\frac{1}{2}dx - \mathlarger{ \int\frac{1}{2}dx}$

Example of large integral


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