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The equation \(\sqrt{x+4}\) - \(\sqrt{x-3}\) + 1 = 0 has ..........A) no root B) one real root C) one real root and one imaginary root D) two imaginary roots |
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Answer» Correct option is (A) no root Given equation is \(\sqrt{x+4}-\sqrt{x-3}+1=0\) ______________(1) \(\Rightarrow\) \(\sqrt{x+4}+1=\sqrt{x-3}\) \(\Rightarrow\) \((\sqrt{x+4}+1)^2=x-3\) (By squaring both sides) \(\Rightarrow x+4+2\sqrt{x+4}+1=x-3\) \(\Rightarrow2\sqrt{x+4}=x-3-x-5\) \(\Rightarrow2\sqrt{x+4}=-8\) \(\Rightarrow\) 4 (x+4) = 64 (By squaring both sides) \(\Rightarrow\) x+4 = \(\frac{64}4\) = 16 \(\Rightarrow\) x = 16 - 4 = 12 Put x = 12 in equation (1), we get \(\sqrt{12+4}-\sqrt{12-3}+1=0\) \(\Rightarrow\) \(\sqrt{16}-\sqrt{9}+1=0\) \(\Rightarrow\) 4 - 3 + 1 = 0 \(\Rightarrow\) 2 = 0 (Not satisfied) Hence, x = 12 is not a solution of given equation. Hence, the given equation has no root. Correct option is A) no root |
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