Question

3-81x^3 factorise the following equation

Answer 1

$Given \:3 - 81x^{3}\\= 3 - 3 \times 27x^{3} \\= 3(1- 3^{3}x^{3} ) \\ = 3[ 1^{3} - (3x)^{3}] \\= 3(1-3x)[1^{2} + 1 \times 3x + (3x)^{2}]$

$\blue {( By \: Algebraic \:Identity )}$

$\boxed{\pink { a^{3} - b^{3} = (a-b)(a^{2}+ab+b^{2}) }}$

$= 3(1-3x)(1 + 3x + 9x^{2})$

Therefore.,

$\red { Factors \:of \:3 - 81x^{3}}\\\green {=3(1-3x)(1 + 3x + 9x^{2})}$

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Answer 2

1. answer good Quest. and I l9ve it it