Question

[quang ngo]

tìm x , biết :

a , (x-3)*(x^2+3x+9)+x(x+2)*(2-x)=1

b, (x+1)^3-(x-1)^3-6*(x-1)^2=-10

Answer 1

[luuthianhhuyen]

câu a x = 7

Câu b x = -0,5

k nha

Answer 2

[Nguyễn Việt Hoàng]

\(\text{a , (x-3).(x^2+3x+9)+x(x+2).(2-x)=1 }\)

=(x³-3³)+x(4-x²)=1

=x³-27+4x-x³=1

4x-27=1

4x=28

x=7

\(\text{b, (x+1)^3-(x-1)^3-6.(x-1)^2=-10}\)

=-0,5