Find the square of : 3 + 2 5 - Vidyadip

Question

Find the square of : $3 + 2\sqrt5$

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Answer

$( 3 + 2\sqrt5 )^2$
$= 3^2 + 2( 3 )( 2\sqrt5) + ( 2\sqrt5 )^2$
$= 9 + 12\sqrt5 + 20$
$= 29 + 12\sqrt5$

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