### Home > CALC3RD > Chapter Ch9 > Lesson 9.1.2 > Problem 9-25

9-25.

A square plot of land to a point

*on side*

*, and from there to point*

*. (Point*

*cannot be point*

*or point*

*.) The cost of laying the pipe is*

*to point*

*(since it must be laid underground) and*

Let .

Now write expressions for

*and*

*.*

The function for the cost is .

Once you have written the cost function in terms of , differentiate and determine the value of

*that yields a miniumum.*

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Note: This is not the answer to the question being asked.