Conjectures prove or disprove Prove this conjecture by giving 3 examples or disprove it using 1 counterexample. 
Prove the function $f(x) = \sqrt{x-2}$, over the domain $1 \leq x \leq 6$ will give a real solution.
Please help me with full explanation. Thank you! :)

Hint: Compute $f(1){}{}{}{}{}$.
Edit 1: It was estabilished that the OP realises that only non-negative real numbers can be square-rooted.
Having this in my mind, when you replace $x$ with $1$ in the expression that defines $f$, what  number will you be trying to find the square root of?
Edit 2: You get $f(1)=\sqrt{1-2}=\cdots$
