4. Evaluate the integral dydx.

(四)請 用 γ、θ、及 Q-函數來表示此通訊系統的錯誤機率Pe。這裡的 γ＝Eb/N0 是每位元的訊雜比（signal-to-noise ratio, SNR），且對 M 符元 / 訊號源（M-ary signaling）而言， 。 （8 分）

1. Find the limit.

2. Find (x sin x).

3. Evaluate the integral

5. Consider the region bounded by the graphs of y = In x, y = 0, and x = e. Find the volume of the solid formed by revolving the region about the x-axis.

6. Let y = (sin a)x, sin x ＞ 0. Find

7. Assume that constants a and b are positive. Find equations for all horizontal asymptotes for the graph of .

8. We say that the two commodities are substitute commodities if a decrease in the demand for one results in an increase in the demand for the other. Con- versely, two commodities are referred to as complementary commodities if a decrease in the demand for one results in a decrease in the demand for the other as well. Suppose that the demand equations that relate the quantities demanded x and y to the unit prices p and q of the commodities A and B respectively are  given by . Are A and B substitute, complementary or neither? 

(a) (4 分) Show that f is continuous at x = 0.

(b)(4分)Find f'(x) for x≠0.