text: module.export = exports = {
  	rotate: rotate,
  	dotProduct: dotProduct,
  	magnitude: magnitude,
  	normalize: normalize
  }
  
  function rotate(a, angle) {
  	return {
  		x: a.x * Math.cos(angle) - a.y * Math.sin(angle),
  		y: a.x * Math.sin(angle) - a.y * Math.cos(angle)
  	}
  }
  
  function dotProduct(a, b) {
  	return a.x * b.x + a.y * b.y;
  }
  
  function magnitude(a) {
  	return Math.sqrt(a.x * a.x + a.y * a.y);
  }
  
  function normalize(a) {
  	var magnitude = magnitude(a);
  	return {x: a.x/magnitude, y: a.y/magnitude}
  }