Please help me with this differential calculus question

If the total cost (in £s) function is given by |

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TC = 2Q^{2 }+ 158Q - 12000

where Q is the quantity produced

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(a) | What Q would minimise total costs? | | |

Give your answer to** 2 decimal places.** | | | |

(b) | Use your value in (a) to find the minimum value for total costs. |

Give your answer to the** nearest**
pound.
If anyone could go through how to get the answer with me I would be extremely grateful. | | | |

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Re: Please help me with this differential calculus question

for the cost function you posted, the minimum cost will occur when Q = 0 ... which leads me to believe that the cost function has a sign typo.