From 29d24dba7381a13af1ff88ff5feb0dc7f538a0b6 Mon Sep 17 00:00:00 2001 From: eggy Date: Thu, 29 Oct 2020 15:06:42 -0400 Subject: [PATCH] math: interval lines --- docs/mhf4u7.md | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/docs/mhf4u7.md b/docs/mhf4u7.md index 3952959..b896b0f 100644 --- a/docs/mhf4u7.md +++ b/docs/mhf4u7.md @@ -510,6 +510,16 @@ The $n$th derivative of $f(x)$ is $f^{(n)}(x)$, and is the derivative of the $n- !!! example The second derivative of an object's position with respect to time is its acceleration. See [SL Physics A#Displaying motion](/sph3u7/#displaying-motion) for more information. +### Interval charts + +To identify the positive or negative regions of an equation, an interval line or chart can be used. To do so: + +1. Factor the equation as much as possible and identify the x-intercepts. +2. Place the x-intercepts on a line. +3. Solve for any value in between two x-intercepts. That region is the sign of the solved value. +4. When crossing an x-intercept, if the degree of that factor is even, the sign stays the same; otherwise, it alternates. +5. Repeat for every other region. + ## Resources - [IB Math Analysis and Approaches Syllabus](/resources/g11/ib-math-syllabus.pdf)