If, X = $\sqrt{\sqrt{\frac{10+3\sqrt{11}}{10-3\sqrt{11}}}}$ Then Find the value of $X^4 + \frac{1}{X^4}$ ?

Simplify $\frac{81x^2-49y^2}{9x+7y}$

$\frac{(a-b{)}^3+(b-c{)}^3+(c-a{)}^3}{3(a-b)(b-c)(c-a)}=?$

What is the value of above expression?

If $a+b+c=13$ and $ab+bc+ca=54$, then $a^3+b^3+c^3-3abc$ is equal to:

Simplify:

${\left(\mathrm{a}+\mathrm{b}-\mathrm{c}+\mathrm{d}\right)}^2-{\left(\mathrm{a}-\mathrm{b}+\mathrm{c}-\mathrm{d}\right)}^2=?$

What is the simplified value of $\frac{(2.7{)}^3+(1.3{)}^3}{(2.7{)}^2-2.7\times 1.3+(1.3{)}^2}?$

Expand : ${\left(\mathrm{W}-9\right)}^2$

1. $\left({\mathrm{W}}^2-9\mathrm{W}+81\right)$

2. $\left({\mathrm{w}}^2-9\mathrm{W}+18\right)$

3. $\left({\mathrm{W}}^2-18\mathrm{W}+81\right)$

4. $\left({\mathrm{W}}^2-18\mathrm{W}-81\right)$