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Find the roots of the quadratic equation $$bx^{2}-2ax+a=0$$
If the quadratic equation is of typeΒ $$Ax^+Bx+C=0$$ then the roots of the quadratic equation are given by
$$x = \dfrac{-B\pm\sqrt{B^2 - 4AC}}{2A}$$
ComparingΒ $$Ax^+Bx+C=0$$ withΒ $$bx^{2}-2ax+a=0$$, A = b,Β B = -2a,Β C = a
Hence, the roots = $$\dfrac{2a\pm\sqrt{4a^2 - 4ba}}{2b}$$
x = $$\dfrac{a\pm\sqrt{a^2 - ba}}{b}$$
Let $$x_{1}$$ =Β $$\dfrac{a-\sqrt{a^2 - ba}}{b}$$,Β Β $$x_{2}$$ =Β $$\dfrac{a+\sqrt{a^2 - ba}}{b}$$
RationalizingΒ $$x_{1}$$ =Β $$\dfrac{a-\sqrt{a^2 - ba}}{b}$$
$$\Rightarrow$$ $$x_{1}$$ =Β $$\dfrac{a-\sqrt{a^2 - ba}}{b}*\dfrac{a+\sqrt{a^2 - ba}}{a+\sqrt{a^2 - ba}}$$
$$\Rightarrow$$ $$x_{1}$$ =Β $$\dfrac{a^2-(a^2 - ba)}{b*(a+\sqrt{a^2 - ba})}$$
$$\Rightarrow$$ $$x_{1}$$ =Β $$\dfrac{ab}{b*(a+\sqrt{a^2 - ba})}$$
$$\Rightarrow$$ $$x_{1}$$ =Β $$\dfrac{a}{a+\sqrt{a^2 - ba}}$$
$$\Rightarrow$$ $$x_{1}$$ =Β $$\dfrac{a}{a+\sqrt{a}*\sqrt{a - b}}$$
$$\Rightarrow$$ $$x_{1}$$ =Β $$\dfrac{\sqrt{a}}{\sqrt{a}+\sqrt{a - b}}$$
Similarly,Β $$x_{2}$$ =Β $$\dfrac{\sqrt{a}}{\sqrt{a}-\sqrt{a - b}}$$
Therefore, x =Β $$\dfrac{\sqrt{a}}{\sqrt{a}\pm\sqrt{a - b}}$$. Hence, option C is the correct answer.Β
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