Question

[Duy Dũng Trần]

1) (x+1)(x+2)(x+3)(x+4)=24 2) (x+1)(x+2)(x+3)(x+4)(x+5) = 40 3) (x^2+x)^2 +4( x^2 +x)-12=0 4) (x+1)^2 + (x+2)^3 + (x+3)^4 =2

Answer 1

[Nguyễn Lê Phước Thịnh]

1: 

\(\Leftrightarrow\left(x^2+5x+6\right)\left(x^2+5x+4\right)=24\)

\(\Leftrightarrow\left(x^2+5x\right)^2+10\left(x^2+5x\right)=0\)

\(\Leftrightarrow x^2+5x=0\)

=>x=0 hoặc x=-5

3: \(\Leftrightarrow\left(x^2+x+6\right)\left(x^2+x-2\right)=0\)

=>(x+2)(x-1)=0

=>x=-2 hoặc x=1