fixes #997 (#998)

bpetermann · martin-henz · web-flow · commit 7b7e2a50027a · 2024-06-30T13:39:28.000+08:00
Co-authored-by: Martin Henz &lt;henz@comp.nus.edu.sg&gt;
diff --git a/xml/chapter2/section1/subsection4.xml b/xml/chapter2/section1/subsection4.xml
@@ -411,7 +411,7 @@ function the_trouble_maker(xl, xu, yl, yu) {
     const p2 = xl * yu;
     const p3 = xu * yl;
     const p4 = xu * yu;
-    make_interval(math_min(p1, p2, p3, p4),
+    return make_interval(math_min(p1, p2, p3, p4),
                   math_max(p1, p2, p3, p4));
 }
 function mul_interval(x, y) {  

Original file line number	Diff line number	Diff line change
`@@ -411,7 +411,7 @@ function the_trouble_maker(xl, xu, yl, yu) {`
`411`	`411`	`const p2 = xl * yu;`
`412`	`412`	`const p3 = xu * yl;`
`413`	`413`	`const p4 = xu * yu;`
`414`		`- make_interval(math_min(p1, p2, p3, p4),`
	`414`	`+ return make_interval(math_min(p1, p2, p3, p4),`
`415`	`415`	`math_max(p1, p2, p3, p4));`
`416`	`416`	`}`
`417`	`417`	`function mul_interval(x, y) {`