The value of $$4 + {1 \over {5 + {1 \over {4 + {1 \over {5 + {1 \over {4 + ......\infty }}}}}}}}$$ is :
Solution
$y = 4 + {1 \over {5 + {1 \over y}}}$<br><br>$\Rightarrow y = 4 + {y \over {5y + 1}}$<br><br>$\Rightarrow 5{y^2} - 20y - 4 = 0$<br><br>$\Rightarrow y = {{20 \pm \sqrt {400 + 80} } \over {10}}$<br><br>$\Rightarrow y = {{20 \pm 4\sqrt {30} } \over {10}},y > 0$<br><br>$\therefore$ $y = {{10 + 2\sqrt {30} } \over 5}$
About this question
Subject: Mathematics · Chapter: Complex Numbers and Quadratic Equations · Topic: Complex Numbers and Argand Plane
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