{"version":"1.0","provider_name":"Matem\u00e1ticas y sus fronteras","provider_url":"https:\/\/www.madrimasd.org\/blogs\/matematicas","author_name":"Matem\u00e1ticas y sus fronteras","author_url":"https:\/\/www.madrimasd.org\/blogs\/matematicas\/author\/matematicas","title":"Ver para pensar - Matem\u00e1ticas y sus fronteras","type":"rich","width":600,"height":338,"html":"<blockquote class=\"wp-embedded-content\" data-secret=\"h1u4L19T5O\"><a href=\"https:\/\/www.madrimasd.org\/blogs\/matematicas\/2019\/06\/18\/146712\">Ver para pensar<\/a><\/blockquote><iframe sandbox=\"allow-scripts\" security=\"restricted\" src=\"https:\/\/www.madrimasd.org\/blogs\/matematicas\/2019\/06\/18\/146712\/embed#?secret=h1u4L19T5O\" width=\"600\" height=\"338\" title=\"\u00abVer para pensar\u00bb \u2014 Matem\u00e1ticas y sus fronteras\" data-secret=\"h1u4L19T5O\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\" class=\"wp-embedded-content\"><\/iframe><script>\n\/**\n * WordPress inline HTML embed\n *\n * @since 4.4.0\n * @output wp-includes\/js\/wp-embed.js\n *\n * This file cannot have ampersands in it. This is to ensure\n * it can be embedded in older versions of WordPress.\n * See https:\/\/core.trac.wordpress.org\/changeset\/35708.\n *\/\n(function ( window, document ) {\n\t'use strict';\n\n\tvar supportedBrowser = false,\n\t\tloaded = false;\n\n\t\tif ( document.querySelector ) {\n\t\t\tif ( window.addEventListener ) {\n\t\t\t\tsupportedBrowser = true;\n\t\t\t}\n\t\t}\n\n\t\/** @namespace wp *\/\n\twindow.wp = window.wp || {};\n\n\tif ( !! window.wp.receiveEmbedMessage ) {\n\t\treturn;\n\t}\n\n\t\/**\n\t * Receive embed message.\n\t *\n\t * @param {MessageEvent} e\n\t *\/\n\twindow.wp.receiveEmbedMessage = function( e ) {\n\t\tvar data = e.data;\n\n\t\tif ( ! data ) {\n\t\t\treturn;\n\t\t}\n\n\t\tif ( ! ( data.secret || data.message || data.value ) ) {\n\t\t\treturn;\n\t\t}\n\n\t\tif ( \/[^a-zA-Z0-9]\/.test( data.secret ) ) {\n\t\t\treturn;\n\t\t}\n\n\t\tvar iframes = document.querySelectorAll( 'iframe[data-secret=\"' + data.secret + '\"]' ),\n\t\t\tblockquotes = document.querySelectorAll( 'blockquote[data-secret=\"' + data.secret + '\"]' ),\n\t\t\tallowedProtocols = new RegExp( '^https?:$', 'i' ),\n\t\t\ti, source, height, sourceURL, targetURL;\n\n\t\tfor ( i = 0; i < blockquotes.length; i++ ) {\n\t\t\tblockquotes[ i ].style.display = 'none';\n\t\t}\n\n\t\tfor ( i = 0; i < iframes.length; i++ ) {\n\t\t\tsource = iframes[ i ];\n\n\t\t\tif ( e.source !== source.contentWindow ) {\n\t\t\t\tcontinue;\n\t\t\t}\n\n\t\t\tsource.removeAttribute( 'style' );\n\n\t\t\t\/* Resize the iframe on request. *\/\n\t\t\tif ( 'height' === data.message ) {\n\t\t\t\theight = parseInt( data.value, 10 );\n\t\t\t\tif ( height > 1000 ) {\n\t\t\t\t\theight = 1000;\n\t\t\t\t} else if ( ~~height < 200 ) {\n\t\t\t\t\theight = 200;\n\t\t\t\t}\n\n\t\t\t\tsource.height = height;\n\t\t\t}\n\n\t\t\t\/* Link to a specific URL on request. *\/\n\t\t\tif ( 'link' === data.message ) {\n\t\t\t\tsourceURL = document.createElement( 'a' );\n\t\t\t\ttargetURL = document.createElement( 'a' );\n\n\t\t\t\tsourceURL.href = source.getAttribute( 'src' );\n\t\t\t\ttargetURL.href = data.value;\n\n\t\t\t\t\/* Only follow link if the protocol is in the allow list. *\/\n\t\t\t\tif ( ! allowedProtocols.test( targetURL.protocol ) ) {\n\t\t\t\t\tcontinue;\n\t\t\t\t}\n\n\t\t\t\t\/* Only continue if link hostname matches iframe's hostname. *\/\n\t\t\t\tif ( targetURL.host === sourceURL.host ) {\n\t\t\t\t\tif ( document.activeElement === source ) {\n\t\t\t\t\t\twindow.top.location.href = data.value;\n\t\t\t\t\t}\n\t\t\t\t}\n\t\t\t}\n\t\t}\n\t};\n\n\tfunction onLoad() {\n\t\tif ( loaded ) {\n\t\t\treturn;\n\t\t}\n\n\t\tloaded = true;\n\n\t\tvar isIE10 = -1 !== navigator.appVersion.indexOf( 'MSIE 10' ),\n\t\t\tisIE11 = !!navigator.userAgent.match( \/Trident.*rv:11\\.\/ ),\n\t\t\tiframes = document.querySelectorAll( 'iframe.wp-embedded-content' ),\n\t\t\tiframeClone, i, source, secret;\n\n\t\tfor ( i = 0; i < iframes.length; i++ ) {\n\t\t\t\/** @var {IframeElement} *\/\n\t\t\tsource = iframes[ i ];\n\n\t\t\tsecret = source.getAttribute( 'data-secret' );\n\t\t\tif ( ! secret ) {\n\t\t\t\t\/* Add secret to iframe *\/\n\t\t\t\tsecret = Math.random().toString( 36 ).substr( 2, 10 );\n\t\t\t\tsource.src += '#?secret=' + secret;\n\t\t\t\tsource.setAttribute( 'data-secret', secret );\n\t\t\t}\n\n\t\t\t\/* Remove security attribute from iframes in IE10 and IE11. *\/\n\t\t\tif ( ( isIE10 || isIE11 ) ) {\n\t\t\t\tiframeClone = source.cloneNode( true );\n\t\t\t\tiframeClone.removeAttribute( 'security' );\n\t\t\t\tsource.parentNode.replaceChild( iframeClone, source );\n\t\t\t}\n\n\t\t\t\/*\n\t\t\t * Let post embed window know that the parent is ready for receiving the height message, in case the iframe\n\t\t\t * loaded before wp-embed.js was loaded. When the ready message is received by the post embed window, the\n\t\t\t * window will then (re-)send the height message right away.\n\t\t\t *\/\n\t\t\tsource.contentWindow.postMessage( {\n\t\t\t\tmessage: 'ready',\n\t\t\t\tsecret: secret\n\t\t\t}, '*' );\n\t\t}\n\t}\n\n\tif ( supportedBrowser ) {\n\t\twindow.addEventListener( 'message', window.wp.receiveEmbedMessage, false );\n\t\tdocument.addEventListener( 'DOMContentLoaded', onLoad, false );\n\t\twindow.addEventListener( 'load', onLoad, false );\n\t}\n})( window, document );\n<\/script>\n","description":"\u00abEn muchos casos, una demostraci\u00f3n farragosa puede ser sustituida por una geom\u00e9trica an\u00e1loga, tan simple y bella que la veracidad de un teorema es casi vista en una ojeada\u00bb, Martin Gardner, 1973 Los Libros de la Catarata, la Federaci\u00f3n Espa\u00f1ola de Profesores de Matem\u00e1ticas y el Instituto de Ciencias Matem\u00e1ticas del CSIC contin\u00fana su colaboraci\u00f3n editorial con un nuevo t\u00edtulo de la colecci\u00f3n Miradas Matem\u00e1ticas,\u00a0 y\u00a0 esta vez es el turno de Demostraciones visuales en matem\u00e1ticas. Ver para pensar, de Ana Carvajal S\u00e1nchez y Jos\u00e9 Luis Mu\u00f1oz Casado. &nbsp; Ya hemos rese\u00f1ado en Matem\u00e1ticas y sus fronteras los vol\u00famenes que\u2026","thumbnail_url":"http:\/\/www.madrimasd.org\/blogs\/matematicas\/files\/2019\/06\/edition-85486-236x371.jpg"}