Question

Rút gọn :

A = \(\sqrt{9x^4+6x^2+1}-3x^2\)

Answer 1

\(\sqrt{9x^4+6x^2+1}-3x^2\)

\(=\left(3x^2+1\right)-3x^2\)

\(=1\)

Answer 2

\(A=\sqrt{9x^4+6x^2+1}-3x^2\)

\(=\sqrt{\left(3x^2\right)^2+2\cdot3x^2+1}-3x^2\)

\(=\left(3x^2+1\right)-3x^2\)

\(=1\)

Answer 3

\(A=\sqrt{9x^4+6x^2+1}-3x^2\)

=>\(A=\sqrt{\left(3x^2\right)+2.3x^2.1+1^1}-3x^2\)

=>\(A=\sqrt{\left(3x^2+1\right)^2}-3x^2\)

=>\(A=3x^2+1-3x^2\)

=>A=1