Write the coefficients of $x^{2}$ in each of the following: <br/> <br/> (i) $2+x^{2}+x$ <br/> <br/>(ii) $2-x^{2}+x^{3}$ <br/> <br/>(iii) $\frac{\pi}{2} x^{2}+x$ <br/> <br/>(iv) $\sqrt{2} x-1$

Solution:

(i) $2+x^{2}+x$

In the above expression, the coefficient of $x^{2}$ is 1 .

(ii) $2-x^{2}+x^{3}$

In the above expression, the coefficient of $x^{2}$ is $-1$.

(iii) $\frac{\pi}{2} x^{2}+x$

In the above expression, the coefficient of $x^{2}$ is $\frac{\pi}{2}$.

(iv) $\sqrt{2} x-1$, or

$0 x^{2}+\sqrt{2} x-1$

In the above expression, the coefficient of $x^{2}$ is $0 .$