Answer the following with respect to the concept of domain of a real-valued function:

MATHEMATICS · Multi-part · A Level · Mathematics · Algebra and Functions · Algebra and Functions

Problem

Answer the following with respect to the concept of domain of a real-valued function: (i) Define the domain of a function. (ii) Explain, with reason, why the domain of f(x)=1x−3f(x)=\dfrac{1}{x-3} excludes the value x=3x=3. (iii) For g(x)=5−2xg(x)=\sqrt{5-2x}, state the inequality that xx must satisfy so that g(x)g(x) is real and explain your reasoning. (iv) Justify why the expression log⁡10(x+4)\log_{10}(x+4) imposes a different kind of restriction on xx compared to the restrictions in parts (ii) and (iii).

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