Further Reading: Differentiation 1 (Bostock & Chandler) Tangents, normals and stationary points (Bostock & Chandler)
	Practise Questions: Excersise 13C, 13D, 13E, 13F (Differentiation 1) Excersise 14A (Tangents, normals and stationary points)
	introduction to differentiation (s-cool) differentiation (bbc) - nice inter - active stuff! surfing animation
	Calculus 1