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    Can someone please help me with this question below. From differentiation
    The question is At time t minutes after being switched on, the temperature of an oven is theta
    given by theta=190-175 e^ -0.08t

    the answer to the first part was 'find the time taken to reach a temp of 160 was 22min I got that, but I dont think thats relevant for the next part

    find the rate at which the temperature is increasing when theta is 50
    so I plugged in theta and differentiated to find t and got something weird
    I them tried differentiating and then plugging in the value-but that didn't work.

    the answer is 11.2 degrees, unless its wrong :P
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    Differentiate before you substitute the value.

    Show your working.
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    I have checked and the answer is correct.

    You need to find the value of t when theta = 50 and this is probably where you are going wrong.
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    (Original post by Mr M)
    I have checked and the answer is correct.

    You need to find the value of t when theta = 50 and this is probably where you are going wrong.

    ohhhhh :P thank you! that'll explain hah!
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    (Original post by Mr M)
    I have checked and the answer is correct.

    You need to find the value of t when theta = 50 and this is probably where you are going wrong.

    yep 11.2 thanks!
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    (Original post by AishaTara)
    yep 11.2 thanks!
    Good.
 
 
 
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