Question

Tìm x

a) 27x³ + 64 =0

b) -x² -25 + 10x

Answer 1

a,\((3x)^3\)=-64(=)3x=-4(=)x=\(-\frac{4}{3}\)

ý b thiếu đề bài

Answer 2

a)\(27x^3+64=0\)

\(\Rightarrow27x^3=-64\)

\(\Rightarrow x^3=-\frac{64}{27}\)

\(\Rightarrow x^3=\left(-\frac{4}{3}\right)^3\)

\(\Rightarrow x=-\frac{4}{3}\)

Answer 3

a) x= -4/3

b) chiu