Question

In the expansion of ${(x^2-\frac{1}{x})}^2$ find
(i) 4 th term
(ii) middle term
(iii) term independent of $x$

Answer 1

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

$=x^4+{\left(\frac{1}{x}\right)}^2-2x^2\frac{1}{x}$

$=x^4+{\left(\frac{1}{x}\right)}^2-2x$

(i) 4 th term

$=0$

(ii) middle term

$={\left(\frac{1}{x}\right)}^2$

(iii) term independent of x

$=0$