Question

(2x-1)³-4x²(2x-3)=17

Answer 1

$(2x - 1) {}^{3} - 4 {x}^{2} (2x - 3) = 17 \ 8 {x}^{3} - 12 {x}^{2} + 6x - 1 - 8 {x}^{3} + 12 {x}^{2} = 17 \ 6x - 1 = 17 \ 6x = 17 + 1 \ 6x = 18 \ x = 18 div 6 \ x = 3$

Answer 2

$(2x-1)^3-4x^2(2x-3) = 17\\8x^3-12x^2+6x-1-8x^3+12x^2=17\\ 6x-1 =17\\6x=17+1\\6x=18 /:6\\x=3\\(a-b)^3=a^3-3a^2b+3ab^2-b^3$