AP4­2.4.notebook
December 06, 2011
Optimization Day 4
1. Two posts, one 12 ft high and the other
28 feet high, stand 30 feet apart. They are to
be stayed by two wires, attached by a single
stake, running from the ground level to
the top of each post. Where should the stake
be placed to use the least wire?
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AP4­2.4.notebook
2. You are planning to close off a corner of the
first quadrant with a line segment 20 units
long running from (a,0) to (0,b). Show that the
area of the triangle enclosed by the segment
is largest when a = b.
December 06, 2011
3. A tank with a rectangular base and rectangular sides is to be open at the top. It
is to be constructed so that its width is 4 meters
and its volume is 36 cubic meters. If building
the tank costs $10 per square meter for the base
and $5 per square for the sides, what is the cost
of the least expensive tank?
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