| <!DOCTYPE html> | |
| <math> | |
| <mfrac id="mfrac"><mn>1</mn><mn>2</mn></mfrac> | |
| <msqrt id="msqrt"><mi>a</mi><mi>b</mi><mi>c</mi></msqrt> | |
| <mn id="mn4">4</mn> | |
| <mn id="mn5">5</mn> | |
| <mn id="mn6">6</mn> | |
| <mn id="mn7">7</mn> | |
| </math> | |
| <script> | |
| document.body.offsetTop; | |
| var mfrac = document.getElementById("mfrac"); | |
| mfrac.replaceChild(document.getElementById("mn4"), mfrac.lastChild); | |
| mfrac.replaceChild(document.getElementById("mn5"), mfrac.firstChild); | |
| var msqrt = document.getElementById("msqrt"); | |
| msqrt.replaceChild(document.getElementById("mn6"), msqrt.firstChild); | |
| msqrt.replaceChild(document.getElementById("mn7"), msqrt.lastChild); | |
| </script> |