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%\author{}
\title{Projectile on Inclined Plane}
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\frametitle{Projectile on an inclined Plane}
In an inclined plane projectile, we try to analyze a projectile motion when it is projected on an inclined plane.
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Here we have two cases:
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\begin{enumerate}
\item Up the plane
\item Down the plane
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\frametitle{Equations of Inclined projectile}
We will try to resolve the velocity and acceleration according to the co-ordinate system we have selected.
\begin{itemize}
\item $ u_x = u cos(%alpha - %theta) $
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% always starts a comment. So your equation is \item $ u_x = u cos( only and indeed a $ is missing. To add a percent-character you have to use \% instead of %. But note, cos is the product of the three variables c, o and s not the cosine function. The function would be \cos. And \%alpha would also be a product. I don't know, whether this should be \alpha or \text{\%alpha}. Same for %theta.
BTW: Loading deprecated package times before lmodern makes no sense.
Sorry, but I can no longer participate here as the administrator is trampling on my wishes on one of his other platforms.
