Question

(x+5)^2-4x(2x+3)^2-(2x-1)(x+3)(x-3)

Answer 1

\(\left(x+5\right)^2-4x\left(2x+3\right)^2-\left(2x-1\right)\left(x+3\right)\left(x-3\right)\)

\(=x^2+10x+25-4x\left(4x^2+12x+9\right)-\left(2x-1\right)\left(x^2-9\right)\)

\(=x^2+10x+25-16x^3-48x^2-36x-\left(2x^3-18x-x^2+9\right)\)

\(=x^2+10x+25-16x^3-48x^2-36x-2x^3+18x+x^2-9\)

\(=-46x^2-18x+16-18x^3\)

\(=-18x^2-46x^2-8x+16\)