If $2 = x + \frac{1}{1 + \frac{1}{3 + \frac{1}{4}}}$,then the value of $x$ is

$7 \frac{1}{2}-\left[2 \frac{1}{4} \div\left\{1 \frac{1}{4}-x\left(1 \frac{1}{2}-\frac{1}{3}-\frac{1}{6}\right)\right\}\right]=3$. Find the value of $x$.

$15 \frac{2}{3} \times 3 \frac{1}{6} + 6 \frac{1}{3} = 11 \frac{7}{18} + ?$

If $a^{2}+b^{2}-c^{2}=2(a-b-c)-3,$ then the value of $4a-3b+5c$ is

The value of $(3+\sqrt{8})+\frac{1}{3-\sqrt{8}}-(6+4 \sqrt{2})$ is

Which of the following is the $CORRECT$ rationalised form of $\frac{15}{\sqrt{5}+2} ?$