Question

Square of 9.................

Answer 1

(9)²

9×9

81

so, square of 9 is 81

here is your answer

Answer 2

$\huge{\mathfrak{\underline{Answer}:-}}$

81

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$\huge{\mathfrak{\underline{Solution}:-}}$

$\: \: \: \: \: \sf 9 {}^{2} \\ \sf \to (10 - 1) {}^{2} \\ \sf \to 10 {}^{2} - 2 \times 10 \times 1 + 1 {}^{2} \\ \sf \to 100 - 20 + 1 \\ \to \sf 80 + 1 \\ \\ \huge\sf \to \boxed{ \blue{ \sf {81}}}$

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