Problem on Functional Expressions

In college algebra tutorial , the word expression is a term for any well-formed combination of mathematical symbols[citation needed]. An algebraic expression is only a phrase, not a whole sentence, so it cannot contain an equality sign (=). For example,x2 + 3x −4 is an expression, while y = x2 + 3x − 4 is an equation but not an expression. Neither is (x) / y an expression because the parentheses are not balanced.

Being an expression is a syntactic concept – the meaning of the variables is irrelevant, but different fields have different notions of validity.See formal language for how expressions are constructed, and formal semantics for meaning.Let's see an example from algebraic expressions word problems



Question:-

The functions f(x)=2x and g(x)=x²+1

Find the value of each expression ,the expression is f[g(3)]


Answer:-

Let's see how to evaluate the expression

f(x)=2x

g(x)=x²+1

g(3)=3²+1 = 9+1 = 10

So,f[g(3)]= f(10)

We know f(x) = 2x

So f(10) = 2 . 10 = 20

So f[g(3)] = 20 Answer