What is the real domain of the function \(f(x)=\sqrt{x+10}\)?

Correct answer: \([-10,\infty)\)

For a real square root, the expression inside the root cannot be negative. Hence, \(x+10\ge 0\), so \(x\ge -10\). Therefore, the real domain is \([-10,\infty)\). Option C excludes \(-10\), but at \(x=-10\), \(f(x)=\sqrt{0}=0\) is defined. Exam tip: For a square-root function, set the radicand \(\ge 0\) before solving the inequality.