Question

(X^2-6x+9)^2-15(x^2-6x+10)=1

(X^2+1)^2+3x (x^2+1)+2x^2=0

Answer 1

a: \(\Leftrightarrow\left(x^2-6x+9\right)^2-15\left(x^2-6x+9+1\right)-1=0\)

\(\Rightarrow\left(x^2-6x+9\right)^2-15\left(x^2-6x+9\right)-16=0\)

\(\Leftrightarrow\left(x^2-6x+9-16\right)\left(x^2-6x+9+1\right)=0\)

\(\Leftrightarrow x^2-6x-7=0\)

=>(x-7)(x+1)=0

=>x=7 hoặc x=-1

b: \(\left(x^2+1\right)^2+3x\left(x^2+1\right)+2x^2=0\)

\(\Leftrightarrow\left(x^2+2x+1\right)\left(x^2+x+1\right)=0\)

\(\Leftrightarrow\left(x+1\right)^2=0\)

=>x+1=0

hay x=-1