Partial Derivatives Word Problem

[MAM]

Partial Derivatives Word Problem--HELP!

The function S(w, h) = 15.63w^0.425h^0.725 gives the approximate surface area (in square inches) of a person h inches tall who weighs w pounds.

a. A boy grows taller while maintaining a weight of 130 pounds. At what rate is his surface area increasing when he's 5'4" tall? (Give your answer in units.)

b. Now at his full height of 5'9", he goes to the gym and bulks up. At what rate is his body surface increasing when he reaches 140 pounds?

 

[Deleted member 4993]

The function S(w, h) = 15.63w^0.425h^0.725 gives the approximate surface area (in square inches) of a person h inches tall who weighs w pounds.

a. A boy grows taller while maintaining a weight of 130 pounds. At what rate is his surface area increasing when he's 5'4" tall? (Give your answer in units.)

δS/δh = ???


b. Now at his full height of 5'9", he goes to the gym and bulks up. At what rate is his body surface increasing when he reaches 140 pounds?

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