Related Rates

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Related Rates

• There will be a rate you know, say dA/dt -2.
• There will be a rate you want to know, say dB/dt,
  when (need to be given some information here,
  e.g. when B4).
• Write an equation relating A and B (using
  formulas from the flyleaf or similar triangles,
  etc.), e.g. A2 B2 25.
• Differentiate both sides with respect to t 2A
  dA/dt 2B dB/dt 0.
• Figure out what all the values are except the
  rate you want. E.g. here B4, so from A2 B2
  25, it follows that A3.
• Plug these values in and solve for the rate you
  want 23 (-2) 24 dB/dt 0, so dB/dt
  -2/3.