 Ch 2. Derivatives I Multimedia Engineering Math DerivativeFormulas TrigonometricFunctions Differentiability ChainRule ImplicitDifferentiation
 Chapter 1. Limits 2. Derivatives I 3. Derivatives II 4. Mean Value 5. Curve Sketching 6. Integrals 7. Inverse Functions 8. Integration Tech. 9. Integrate App. 10. Parametric Eqs. 11. Polar Coord. 12. Series Appendix Basic Math Units Search eBooks Dynamics Statics Mechanics Fluids Thermodynamics Math Author(s): Hengzhong Wen Chean Chin Ngo Meirong Huang Kurt Gramoll ©Kurt Gramoll MATHEMATICS - CASE STUDY Introduction Brightness of Delta Cephei Albert, astronomy amateur, notices that the brightness of Delta Cephei periodically increases and decreases. He wonders how fast does its brightness changes at time equals 1day? What is known: The brightness cycles every 5 days The brightness of the star is modeled by the function: B(t) = 4 + 0.35 sin(2πt/b) The time, t, is 1 day. Questions How fast is the brightness changing after a day? Approach Applying the chain rule to find the derivative of the brightness.