The value of integral \[\int\limits_{ – \frac{\pi }{2}}^{\frac{\pi }{2}} {\left( {{\text{x}}\cos {\text{x}}} \right){\text{dx}}} \] is A. 0 B. \[\pi – 2\] C. \[\pi \] D. \[\pi + 2\]

”0″
”[pi
” option3=”\[\pi \]” option4=”\[\pi + 2\]” correct=”option1″]

The correct answer is $\boxed{\pi}$.

To evaluate the integral, we can use the following trigonometric identity:

$$\sin^2(x) + \cos^2(x) = 1$$

We can then substitute $u = \sin(x)$ to get:

$$\int \sin^2(x) \, dx = \int \frac{1 – \cos^2(x)}{2} \, dx = \frac{x}{2} – \frac{\sin(2x)}{4} + C$$

where $C$ is an arbitrary constant.

We can then substitute back to get:

$$\int \sin^2(x) \, dx = \frac{x}{2} – \frac{\sin(2x)}{4} + C$$

Now, we can evaluate the integral $\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \sin^2(x) \, dx$. We get:

$$\begin{align}
\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \sin^2(x) \, dx &= \left[ \frac{x}{2} – \frac{\sin(2x)}{4} \right]_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \
&= \frac{\pi}{2} – \frac{\sin(\pi)}{4} – \left( \frac{-\pi}{2} – \frac{\sin(-\pi)}{4} \right) \
&= \frac{\pi}{2} + \frac{\pi}{4} \
&= \pi
\end{align
}$$

Therefore, the value of the integral $\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \left( {{\text{x}}\cos {\text{x}}} \right){\text{dx}}$ is $\boxed{\pi}$.

The other options are incorrect because they do not represent the correct value of the integral.

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