Problem $1$

Find the value of the third non$-$zero term in the binomial series expansion of $f(x)=\sqrt[\phantom{2}]{1x}.$

$($a$)-\frac{1}{2}{x}^2$

$($b$))-\frac{1}{8}{x}^2$

$($c$)\frac{1}{8}{x}^2$

$($d$)\frac{1}{2}{x}^2$

$($e$)\frac{3}{8}{x}^2$

Problem $2$

$1\frac{1}{2}{x}^{}\frac{1}{2}\frac{1}{2}(-\frac{1}{2})$

$=(1x{)}^{\frac{1}{2}}\frac{\frac{1}{2}(\frac{1}{2}-1)}{2!}-\frac{1}{4}*\frac{1}{2}=$