diff --git a/doc/ImuFactor.lyx b/doc/ImuFactor.lyx
index d9cd35584b..0922a3e9c7 100644
--- a/doc/ImuFactor.lyx
+++ b/doc/ImuFactor.lyx
@@ -398,7 +398,7 @@ The local coordinates
  and note that 
 \begin_inset Formula 
 \[
-\frac{d\Phi_{R_{0}}\left(\omega t\right)}{dt}\biggr\vert_{t=0}=\frac{dR_{0}\exp\left(\Skew{\omega t}\right)}{dt}\biggr\vert_{t=0}=R_{0}\Skew{\omega}
+\frac{d\Phi_{R_{0}}\left(\omega t\right)}{dt}\biggr\vert_{t=0}=\frac{dR_{0}\exp\left(\Skew{\omega t}\right)}{dt}\biggr\vert_{t=0}=R_{0}\Skew{\omega t}
 \]
 
 \end_inset
diff --git a/doc/ImuFactor.pdf b/doc/ImuFactor.pdf
index f5a25f54f7..0b13c1f594 100644
Binary files a/doc/ImuFactor.pdf and b/doc/ImuFactor.pdf differ