$31$ If $a+b+c=12$ and $ab+bc+ca=22$ find $a^{2}+b^{2}+c^{2}$ $32$ If $a+b+c=12$ and $a^{2}+b^{2}+c^{2}=100$ find ab $+bc+ca$ $33$ If $a^{2}+b^{2}+c^{2}=125$ and ab $+bc+ca=50$ find a $4b⊥$

$29$ $1f\left(x+\dfrac {1} {x}\right)^{2}$ $1$ $1x$ $+$ find $x^{3}+\dfrac {1} {x^{3}}$ $3a$ If $x=5-2\sqrt{6} ,$ find the value of $\sqrt{x} +\dfrac {1} {\sqrt{x} }$ $31$ If $a+b+c=12$ and ab $+bc+ca=22$ find $a^{2}+b^{2}+c$ 2.