# In Equation 7.2, dot is over the subscript

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Edition | Second |
---|---|

Version number | 3.0h |

Submission date | 26 Oct 2016 |

Your name | Kai Kirk |

E-mail address | mailto:kkirk@caltech.edu |

Chapter | 7 |

Page number | 7-3 |

Line number | 14 |

Current status | Rejected |

x_d dot = d/dt (x_d) --> the x_d is dotted over the d not the x. should be dotted over the x or the entire x_d?

Response: the equation is correct as written. Exercise 6.1 states that the response to the derivative of a signal is the derivative of the response, and the first equality is making use of this fact.