Answer: tan x + C.
- A x + C
- B tan x + C
- C tan x - x + C
- D tan x + x + C
Correct answer: B. tan x + C
Explanation: 1 + tan²x = sec²x. Integral of sec²x = tan x + C.
The exact area under the curve from a to b (shaded) is approximated by a few rectangles, the Riemann sum idea behind the definite integral.