Question

A= 11√x+5

Tìm x để A = 6

Answer 1

\(A=11\sqrt{x+5}\left(đk:x\ge-5\right)\)

\(A=6\Leftrightarrow11\sqrt{x+5}=6\)

\(\Leftrightarrow\sqrt{x+5}=\dfrac{6}{11}\Leftrightarrow x+5=\dfrac{36}{121}\)

\(\Leftrightarrow x=-\dfrac{569}{121}\left(tm\right)\)

Answer 2

ĐKXĐ: \(x\ge0\)

\(A=11\sqrt{x}+5=6\)

\(\Leftrightarrow11\sqrt{x}=1\Leftrightarrow x=\dfrac{1}{11}\)

\(\Leftrightarrow x=\dfrac{1}{121}\left(tm\right)\)