In the theory of relativity, the energy of a particle is
$$ E = \sqrt{m{_0}^2c^4 + h^2c^2/ \lambda^2} $$
where $ m_0 $ is the rest mass of the particle, $ \lambda $ is its wave length, and $ h $ is Planck's constant. Sketch the graph of $ E $ as a function of $ \lambda $. What does the graph say about the energy?
Applications of Differentiation
Summary of Curve Sketching