Calculus
posted by sh .
To construct a tincan, V=32pi m^3, The cost per square meter of the side is half of the top and bottom of can. What are the dimensions and the cost?
V=πr²h=32pi SA=2πr²+2πrh
h=32/r²
Domain={r>o}
Let x be the cost, I subbed 32/r² for h
C=f(r)=2πxr²+(32xπ/r)
f'(r)=4πxr + 32xπ/r²
common denominator
f'(r)=(4πxr³+ 32xπ)/r²
I factored, it, r=2, which is not in the domain.
Where did it go wrong?
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