প্রতিসম মূল সংক্রান্ত

দ্বিঘাত সমীকরণের একটি মূল 11+3\frac{1}{1+\sqrt{-3}} হলে সমীকরণটি হবে-

DU 09-10

11+3=11+3i=1(13i)(1+3i)(13i)=13i13i+3i3i2=13i13i2=13i1+3=13i4=1434i \begin{aligned} & \frac{1}{1+\sqrt{-3}} \\ = & \frac{1}{1+\sqrt{3} i} \\ = & \frac{1(1-\sqrt{3} i)}{(1+\sqrt{3} i)(1-\sqrt{3} i)} \\ = & \frac{1-\sqrt{3} i}{1-\sqrt{3} i+\sqrt{3} i-3 i^{2}} \\ = & \frac{1-\sqrt{3} i}{1-3 i^{2}} \\ = & \frac{1-\sqrt{3} i}{1+3} \\ = & \frac{1-\sqrt{3} i}{4} \\ = & \frac{1}{4}-\frac{\sqrt{3}}{4} i \end{aligned}

অন্যমূলটি 14+34i \frac{1}{4}+\frac{\sqrt{3}}{4} i

আমরা জানি,

x2 x^{2}- (মূল এর যোগফল) + মূলের গুনফল = 0

=x2(14+34i+1434i)x+(14+34)(1434i)=x2(14+14)x+116316i2=0=x2(1+14)x+116+316=0=x224x+1+316=0=x212x+416=0 \begin{array}{l}=x^{2}-\left(\frac{1}{4}+\frac{\sqrt{3}}{4} i+\frac{1}{4}-\frac{\sqrt{3}}{4} i\right) x+\left(\frac{1}{4}+\frac{\sqrt{3}}{4}\right)\left(\frac{1}{4}-\frac{\sqrt{3}}{4} i\right) \\ =x^{2}-\left(\frac{1}{4}+\frac{1}{4}\right) x+\frac{1}{16}-\frac{3}{16} i^{2}=0 \\ =x^{2}-\left(\frac{1+1}{4}\right) x+\frac{1}{16}+\frac{3}{16}=0 \\ =x^{2}-\frac{2}{4} x+\frac{1+3}{16}=0 \\ =x^{2}-\frac{1}{2} x+\frac{4}{16}=0 \\\end{array}

x212x+14=04x242x+1=04x22x+1=0 \begin{array}{l}x^{2}-\frac{1}{2} x+\frac{1}{4}=0 \\ 4 x^{2}-\frac{4}{2} x+1=0 \\ 4 x^{2}-2 x+1=0\end{array}

প্রতিসম মূল সংক্রান্ত টপিকের ওপরে পরীক্ষা দাও