Calculate the area under the curve y=e^-x above the x axis on the interval [1, infinity).

Question

a. infinity
b. 0
c. -1/e
d. 1/e
e. none of the above

Answer 1

integral e^-x dx = -e^-x

so
-e^-oo - (-e^-1)
= 0 + 1/e