The problem here is relatively simple...I just need to confirm something:(adsbygoogle = window.adsbygoogle || []).push({});

A + B - C = D, in which B is a function of A and C is constant.

dD/dA = 1 + dB/dA for the derivative

To find a min/max of D for certain angles of A,

dD/dA = 0 = 1 + dB/dA

dB/dA = -1

dB = -dA

B = -A, which would imply that D is a min/max where B = -A and dB/dA = -1

D_{min/max}= A - A - C

D_{min/max}= -C, and thus D is a min/max where it is equivalent to -C.

Was my mathematics wrong anywhere in there?

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# Homework Help: Minimum and maximum of an equation

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