Question
Find the square of : $\sqrt5 - 2$
✓
Answer
$( \sqrt5 - 2 )^2$
$= ( \sqrt5 )^2 - 2( \sqrt5 )( 2 ) + ( 2 )^2$
$= 5 - 4\sqrt5 + 4$
$= 9 - 4\sqrt5$
$= ( \sqrt5 )^2 - 2( \sqrt5 )( 2 ) + ( 2 )^2$
$= 5 - 4\sqrt5 + 4$
$= 9 - 4\sqrt5$
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