Giải thích các bước giải:
$\begin{split}a.x^4+3x^2-8&=(x^4+2x^2.\dfrac 32+\dfrac 94)-\dfrac{41}{4}\\&=(x^2+\dfrac 32)^2-\dfrac{41}{4}\\&=(x^2+\dfrac 32-\dfrac{\sqrt{41}}{2})(x^2+\dfrac 32+\dfrac{\sqrt{41}}{2})\end{split}$
$\begin{split} 24x^2-17x-3&=24(x^2-\dfrac{17}{24}x)-3\\ &=24(x^2-2x.\dfrac{17}{48}+(\dfrac{17}{48})^2)-\dfrac{577}{96}\\&=24(x-\dfrac{17}{48})^2-\dfrac{577}{96}\\&=24((x-\dfrac{17}{48})^2-\dfrac{577}{2034})\\&=24(x-\dfrac{17}{48}-\dfrac{\sqrt{577}}{48})(x-\dfrac{17}{48}+\dfrac{\sqrt{577}}{48})\end{split}$