Question

Answer 1

Bài 1:

a: ĐKXĐ: \(2x+1\ne0\)

=>\(2x\ne-1\)

=>\(x\ne-\dfrac{1}{2}\)

b: ĐKXĐ: \(x^2+2x\ne0\)

=>\(x\left(x+2\right)\ne0\)

=>\(\left\{{}\begin{matrix}x\ne0\\x+2\ne0\end{matrix}\right.\)

=>\(x\notin\left\{0;-2\right\}\)

c: ĐKXĐ: \(x^2-9\ne0\)

=>\(x^2\ne9\)

=>\(x\notin\left\{3;-3\right\}\)

d: ĐKXĐ: \(8x^3-1\ne0\)

=>\(x^3\ne\dfrac{1}{8}\)

=>\(x\ne\dfrac{1}{2}\)

e: ĐKXĐ: \(x^2+4x+4\ne0\)

=>\(\left(x+2\right)^2\ne0\)

=>\(x+2\ne0\)

=>\(x\ne-2\)