Q7

Which of the following definite integrals has a positive value?

A. $\displaystyle\int_{-1/2}^{1/2}x^3(1+\cos x)\,dx$

B. $\displaystyle\int_{-1/2}^{1/2}\frac{\sin^{-1}x}{1+x^4}\,dx$

C. $\displaystyle\int_{-1/2}^{1/2}\frac{\cos^{-1}x}{e^{-x^2}}\,dx$

D. $\displaystyle\int_{-1/2}^{1/2}\frac{\tan^{-1}x}{e^x+e^{-x}}\,dx$