The roots of the equation $x^4 - 4x^3 + 6x^2 - 4x + 1 = 0$ are

Let $a$ be the largest real root and $b$ be the smallest real root of the polynomial equation $x^6-6x^5+15x^4-20x^3+15x^2-6x+1=0$. Then $\frac{a^2+b^2}{a+b+1}$ is

The degree of the polynomial $(x+\sqrt{x^4-1})^9+(x-\sqrt{x^4-1})^9$ is

The last digit in $7^{300}$ is

Find the remainder when $3 \times 7^{22} + 2 \times 10^{22} - 44$ is divided by $18$.

$(3+\sqrt{8})^5+(3-\sqrt{8})^5=$