Question

Answer 1

\(\sqrt{4.\left(x-1\right)^2}-5=0\\ đkx\ge1\\ =>2\sqrt{\left(x-1\right)^2}=5\\ =>\sqrt{\left(x-1\right)^2}=\dfrac{5}{2}\\ =>\left(\sqrt{\left(x-1\right)^2}\right)^2=\dfrac{25}{4}\\ =>\left(x-1\right)^2=\dfrac{25}{4}\\ =>\left[{}\begin{matrix}x-1=\dfrac{5}{2}\\x-1=-\dfrac{5}{2}\end{matrix}\right.\\ =>\left[{}\begin{matrix}x=\dfrac{7}{2}\left(thoaman\right)\\x=-\dfrac{3}{2}\left(kothoaman\right)\end{matrix}\right.\\ =>B\)

Answer 2

Chọn B em nhé

Answer 3

\(B\)

Answer 4

Câu này A mới đúng, x xác định trên R