title: How to draw a smooth curve in pgfplots? And how to remove y-axis ticks?
body: <p>I'm preparing a presentation using Latex beamer. I've decided to include a plot.</p>
  
  <p><a href="https://i.stack.imgur.com/yU0sb.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yU0sb.jpg" alt="enter image description here"></a></p>
  
  <p>The middle curve is supposed to be a normal distribution; but it has sharp corners. Why is that?</p>
  
  <p>Also, can I remove the tick marks on the y-axis?</p>
  
  <p>Here is my code:</p>
  
  <pre><code>\begin{frame}
  \begin{tikzpicture}
  \begin{axis}[domain=-1:1]
  \addplot+[no markers] {4*exp(-4*(x+1))};
  \addplot+[no markers] {1/sqrt(2*pi*0.02)*exp(-(x^2)/(2*0.02))};
  \addplot+[no markers] {4*exp(4*(x-1))};
  \end{axis}
  \end{tikzpicture} 
  \end{frame}
  </code></pre>
  
  <p>Thanks</p>