Question

15x-10x elevado a 3-20x elevado a 4+ 25x elevado a 2

Answer 1

$\left(15x-10x\right)^3-\left(20x\right)^4\:+\:\left(25x\right)^2\\\\ = \left(5x\right)^3-\left(20x\right)^4\:+\:\left(25x\right)^2\\\\ = 125x^3-160000x^4+625x^2\\\\ = -160000x^4+125x^3+625x^2$