Functions

• Range of a function is all the possible values of a dependant variable (usually y)
• Domain of a function is all possible values of independant variable (usually x), for which dependant variable (usually y) is defined
• The expression $(f \circ g)(x)$ means "function of a function", and can be rewritten as $f(g(x))$. To solve it, we need to put the equation, that describes function g(x), instead of independant variable at function f(x).
• A function is even if $f(-x)=$$f(x)$ for all x in the domain of f
• A function is odd if $f(-x)=$$-f(x)$ for all x in the domain of f.
• Solve for x means to isolate x - so on one side of equation there will be only x.