\(a,\left(2x^3-27x^2+115x-150\right)\left(x-5\right)\)
\(=x\left(2x^3-27x^2+115-150\right)-5\left(2x^3-27x^2+115-150\right)\)
\(=2x^4-27x^3+115x-150x-10x^3+135x^2-575+750\)
\(=2x^4-37x^3+135x^2-35x+175\)
a, \(\left(2x^3-27x^2+115x-150\right)\left(x-5\right)=2x^4-37x^3+250x^2-725x+750\)
b, đề sai