Set up an integral that represents the length of the curve. then use your calculator to find the length correct to four decimal places. x = y − 2y, 1 ≤ y ≤ 4

If your function is

... x = f(y) = y - 2^y

then its derivative is

... f'(y) = 1 - ln(2)·2^y

and the integral is

_____

If numerical integration is being done, it is convenient to let the calculator use the numerical derivative (f'(t)). The same result is obtained as with the explicit derivative function (1-ln(2)2^t).

to determine the unit cost your would divide the total cost by the number sold.

7 bagels for $4.41       $4.41/7 = $.63 each at fresh side

5 bagels for $3.60         $3.60/5 = $.72 each at value mart