Question

(2x-9)3
please answer my question in step by step and completely​

Answer 1

Step-by-step explanation:

$(2x + 9) {}^{3} \\ putting \: 2x = a \: and \: 9 = b \: we \: get \\ (2x + 9) {}^{3} = ( a + b) {}^{3} \\ = a{}^{3} + b {}^{3} + 3ab \: (a + b) \\ = 2x {}^{3} + 9 {}^{3 } + 3 \times 2x \times 9(2x + 9) \\ = 8x {}^{3} + 729 + 54x(2x + 9) \\ = 8x {}^{3} + 729 + 108x {}^{2} + 486$