From baffc6854bea5b8487a638ae26ba681a0c1aaa20 Mon Sep 17 00:00:00 2001 From: pfatheddin <156558883+pfatheddin@users.noreply.github.com> Date: Sun, 24 Mar 2024 19:41:04 -0400 Subject: [PATCH] Update linearApproximation1.tex https://ximera.osu.edu/mooculus/linearApproximation/exercises/exerciseList/linearApproximation/exercises/linearApproximation1 It is important for them to give the exact interval for underestimate or overestimate when they check the second derivative. --- linearApproximation/exercises/linearApproximation1.tex | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/linearApproximation/exercises/linearApproximation1.tex b/linearApproximation/exercises/linearApproximation1.tex index ec7be36fb..9622a0815 100644 --- a/linearApproximation/exercises/linearApproximation1.tex +++ b/linearApproximation/exercises/linearApproximation1.tex @@ -89,7 +89,7 @@ \begin {hint} Recall: $f''(x)=-\frac{1}{4\cdot x^{\answer{\frac{3}{2}}}}$. -Since $f''(x)<0$ on $(0,\infty)$, the graph of $f$ is concave down. Therefore, the tangent line lies above the graph of $f$, except at $x=9$, where $f(9)=L(9)$. +Since $f''(x)<0$ on $\left(9,\answer{9.5}\right)$, the graph of $f$ is concave down. Therefore, the tangent line lies above the graph of $f$, except at $x=9$, where $f(9)=L(9)$. This means that $L(x)\ge f(x)$. So, $L(9.5)\ge f(9.5)$.