Question

The area of the plane figure bounded by the interval [–5p/6, p] of the x-axis, the graph of the function y = cos x and the segments of the straight lines x = –5p/6 and x = p is -

• A. 3/2
• B. 5/2
• C. 3/4
• D. 7/2

Answer 1

Answer: (D)

7/2

Answer 2

Required area =$\int _ { - 5 \pi / 6 } ^ { \pi } | \cos x |$ dx

= – $\int _ { - 5 \pi / 6 } ^ { - \pi / 2 } \cos x d x$ + –$\int _ { \pi / 2 } ^ { \pi } \cos x d x$= – sin + sin – sin = 7/2.