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NCERT Class XI Mathematics - Complex Numbers and Quadratic Equations - Solutions

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Question : 30 of 52
Marks: +1, -0
3x22x+33\sqrt{3}x^2-\sqrt{2}x+3\sqrt{3} = 0
Solution:  
We have , 3x22x+33\sqrt{3}x^2-\sqrt{2}x+3\sqrt{3} = 0
Comparing the given equation with the general form ax2ax^2 + bx + c = 0,
we get a = 3\sqrt{3} , b = 2-\sqrt{2} , c = 333\sqrt{3}
∴ x = b±b24ac2a\frac{-b\pm\sqrt{b^2-4ac}}{2a} = (2)±(2)24×3×3323\frac{-(-\sqrt{2})\pm\sqrt{(-\sqrt{2})^2-4\times\sqrt{3}\times3\sqrt{3}}}{2\sqrt{3}}
= 2±23623\frac{\sqrt{2}\pm\sqrt{2-36}}{2\sqrt{3}} = 2±3423\frac{\sqrt{2}\pm\sqrt{-34}}{2\sqrt{3}} = 2±i3423\frac{\sqrt{2}\pm i\sqrt{34}}{2\sqrt{3}}
∴ Roots of the given equation are
2+i3423\frac{\sqrt{2}+i\sqrt{34}}{2\sqrt{3}} and 2i3423\frac{\sqrt{2}-i\sqrt{34}}{2\sqrt{3}}
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