Definite integrals

• Expressing Sine and Cosine as Integrals of Bessel Functions
  For x ≥ 0, sine and cosine have exact integral formulas using Bessel functions of orders −1/2 and 1/2, respectively.
• Evaluate the Integral of the Piecewise Function from −2 to 4
  Split the integral at the piecewise breakpoint, evaluate each part, and add the signed results to obtain −4/3.