Question

please answer the question

Answer 1

The given question is of form

$\frac{a^{3} -b^{3}}{a-b}$ where a=secA and b=1

Since $({a^{3} -b^{3}})=({a-b})*({a^{2} +ab+b^{2}})$

⇒ $({a^{3} -b^{3}})/({a-b}) = ({a^{2} +ab+b^{2}})$

So the answer is  $({a^{2} +ab+b^{2}})$

                       = $({(secA)^{2} +secA+1^{2}})$

                       = $({(secA)^{2} +secA+1})$