Sine in LaTeX (\sin)

Where it is used

Sine function, printed upright as a named operator with correct spacing.

Always type \sin rather than sin; the bare letters set as three italic variables multiplied together. The operator adds a thin space before its argument, so \sin x needs no parentheses for a single symbol, while \sin(2x) or \sin\left(\frac{\pi}{2}\right) group longer ones. Powers go right after the command: \sin^2 x + \cos^2 x = 1. Note \sin^{-1} x is the inverse function, not the reciprocal \csc x. Common formulas include the double-angle identity \sin 2\theta = 2\sin\theta\cos\theta and the Taylor series x - x^3/3! + \cdots.

Minimal compilable example

Paste this into an empty .tex file and compile it with pdfLaTeX, XeLaTeX or LuaLaTeX.

\documentclass{article}
\begin{document}
Sine: $\sin$

\[ \sin 2\theta = 2 \sin\theta \cos\theta \]
\end{document}

Related symbols

• Cosine\cos
• Tangent\tan
• Cotangent\cot
• Secant\sec
• Cosecant\csc
• Arcsine\arcsin

Frequently asked questions

How do I write Sine in LaTeX?

Type \sin in math mode, for example $\sin 2\theta = 2 \sin\theta \cos\theta$. It works in plain LaTeX without loading any package.

Which package do I need for \sin?

None. \sin is part of standard LaTeX, so it compiles with nothing in the preamble but the document class.

Can I use \sin in text mode, or only in math mode?

Only in math mode. Outside $...$ LaTeX stops with "Missing $ inserted", so write $\sin$ in running text.