- **Calculus**
(*http://mymathforum.com/calculus/*)

- - **How many solutions to the following equation**
(*http://mymathforum.com/calculus/344541-how-many-solutions-following-equation.html*)

How many solutions to the following equationHow to prove that tanx=10x has exactly 3 roots in the interval (-pi/2, pi/2)? I defined g(x) = tanx-10x. I think I should derive it and use Rolle's theorem and Intermediate value theorem. But I just can't figure out how exactly. Thanks |

Sure looks like infinite roots to me. Did you mean to restrict the domain? |

My bad :o. the domain is restricted to (-pi/2, pi/2) (cannot edit the main post anymore, if a moderator can add the domain to the main post it would be great!) |

Solve $g'(x)=0$ You'll see there are only 2 solutions on your restricted domain. Now apply Rolle's theorem. |

All times are GMT -8. The time now is 12:08 PM. |

Copyright © 2019 My Math Forum. All rights reserved.