Close Help Center ONLYOFFICE Docs Spreadsheet Editor User guides ONLYOFFICE Workspace ONLYOFFICE Groups ONLYOFFICE Docs Mail Server Talk Module ONLYOFFICE Groups Documents Module People Module Commmunity Module CRM Module Projects Module Mail Module Calendar Module ONLYOFFICE Docs All Editors Document Editor Program interface Introducing the Document Editor user interface File tab Home tab Insert tab Draw tab Layout tab References tab Forms tab Collaboration tab Protection tab View tab Plugins tab Basic operations Create a new document or open an existing one Copy/paste text passages, undo/redo your actions Change color scheme Page formatting Set page parameters Show/hide nonprinting characters Insert section breaks Insert headers and footers Insert date and time Insert page numbers Insert line numbers Insert footnotes Insert endnotes Convert endnotes and footnotes Add bookmarks Add watermark Add hyphenation Paragraph formatting Align your text in a paragraph Set up paragraph outline 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Spreadsheet Editor Supported formats of spreadsheets Keyboard shortcuts Presentation Editor Program interface Introducing the Presentation Editor user interface File tab Home tab Insert tab Draw tab Transitions tab Animation tab Collaboration tab View tab Plugins tab Basic operations Create a new presentation or open an existing one Copy/paste data, undo/redo your actions Working with slides Manage slides Set slide parameters Apply transitions Insert headers and footers, notes and handouts Preview your presentation Text formatting Insert and format your text Add hyperlinks Create lists Copy/clear formatting Operations on objects Insert and format autoshapes Insert and adjust images Insert and edit charts Insert and format tables Insert SmartArt objects Draw freehand on a slide Adding animations Creating a motion path animation Insert symbols and characters Fill objects and select colors Manipulate objects on a slide Align and arrange objects on a slide Math equations Insert equations Collaboration Sharing files and folders Co-editing presentations in real time Communicating in real time Commenting presentations Version history Plugins Plugin manager Edit an image Include a video Insert highlighted code Translate text Replace a word by a synonym Communicate while editing Host and schedule Zoom meetings Use AI to write text Add pictures Tools and settings View presentation information Save/print/download your presentation Advanced settings of Presentation Editor View settings and navigation tools Search and Replace Function Spell-checking AutoCorrect features Protecting presentations with a password Enable support for video playback in ONLYOFFICE Desktop Editors Helpful hints About Presentation Editor Supported formats of electronic presentations Keyboard shortcuts PDF Editor Program interface Introducing the PDF Editor user interface File tab Home tab Comment tab View tab Plugins tab Basic operations Open an existing PDF or create a new document Filling out a form Collaboration Sharing files and folders Communicating in real time Commenting PDFs Draw freehand on a PDF Plugins Edit HTML Count words Find a synonym Translate text Read the text out loud Communicate while editing Tools and settings View PDF information Save/print/download your PDF Advanced settings of PDF Editor View settings and navigation tools Search function Helpful hints About PDF Editor Keyboard shortcuts ONLYOFFICE Mobile Apps ONLYOFFICE Documents for iOS ONLYOFFICE Documents for Android ONLYOFFICE Projects for iOS ONLYOFFICE Web Editors Glossary Video FAQ General Technology Pricing Workspace Enterprise Edition Docs Enterprise Edition Docs Developer Edition ONLYOFFICE Groups Connectors Trial period BESSELK Function engineering functions BESSELI function BESSELJ function BESSELK function BESSELY function BIN2DEC function BIN2HEX function BIN2OCT function BITAND function More articles BITLSHIFT function BITOR function BITRSHIFT function BITXOR function COMPLEX function CONVERT function DEC2BIN function DEC2HEX function DEC2OCT function DELTA function ERF function ERF.PRECISE function ERFС function ERFC.PRECISE function GESTEP function HEX2BIN function HEX2DEC function HEX2OCT function IMABS function IMAGINARY function IMARGUMENT function IMCONJUGATE function IMCOS function IMCOSH function IMCOT function IMCSC function IMCSCH function IMDIV function IMEXP function IMLN function IMLOG10 function IMLOG2 function IMPOWER function IMPRODUCT function IMREAL function IMSEC function IMSECH function IMSIN function IMSINH function IMSQRT function IMSUB function IMSUM function IMTAN function OCT2BIN function OCT2DEC function OCT2HEX function The BESSELK function is one of the engineering functions. It is used to return the modified Bessel function, which is equivalent to the Bessel functions evaluated for purely imaginary arguments. Syntax BESSELK(x, n) The BESSELK function has the following arguments: Argument Description x The value at which to evaluate the function, a numeric value greater than 0. n The order of the Bessel function, a numeric value greater than or equal to 0. Notes How to apply the BESSELK function. Examples The figure below displays the result returned by the BESSELK function. Return to previous page Try now for free Try and make your decision No need to install anythingto see all the features in action