If f(x)=3 x and g(x)= 1/x , what is the domain of (g o f)(x)?

The domain is (-∞ , 0)∪(0 , ∞) OR The domain is {x : x ≠ 0}

Step-by-step explanation:

* Lets revise the composite function

- A composite function is a function that depends on another function.

- A composite function is created when one function is substituted into

 another function.

- Ex: f(g(x)) is the composite function that is formed when g(x) is

 substituted for x in f(x).

- In the composition (f ο g)(x), the domain of f becomes g(x).

* Lets solve the problem

∵ f(x) = 3x and g(x) = 1/x

- In (g o f)(x) we will substitute x in g by f

∴ (g o f)(x) = 1/3x

- The domain of the function is all real values of x which make the

  function defined

- In the rational function r(x) = p(x)/q(x) the domain is all real numbers

 except the values of x which make q(x) =0

∵ (g o f)(x) = 1/3x

∵ 3x = 0 ⇒ divide both side by 3

∴ x = 0

∴ The domain of (g o f)(x) is all real numbers except x = 0

∴ The domain is (-∞ , 0)∪(0 , ∞) OR The domain is {x : x ≠ 0}

ratios represent a pattern or relationship that can be scaled.

equivalent ratios are pairs of ratios that represent the same relationship between quantities, and can be generated by multiplying or dividing both quantities in the ratio by the same factor.

in this lesson, students will use double number lines and ratio reasoning to solve ratio problems. by partitioning double number lines into proportionate intervals, students will build an understanding of equivalent ratio relationships as those that are generated by multiplying or dividing two related quantities by the same number. this lesson will build upon students' prior understanding of multiplicative comparisons, number line reasoning and equivalent fractions (while highlighting the difference between equivalent fractions and equivalent ratios); and will build toward future work in this unit on building ratio tables, and work in future grades in proportionality, scaling, and expressing and graphing linear functions.

step-by-step explanation:

ratios represent a pattern or relationship that can be scaled.

equivalent ratios are pairs of ratios that represent the same relationship between quantities, and can be generated by multiplying or dividing both quantities in the ratio by the same factor.

in this lesson, students will use double number lines and ratio reasoning to solve ratio problems. by partitioning double number lines into proportionate intervals, students will build an understanding of equivalent ratio relationships as those that are generated by multiplying or dividing two related quantities by the same number. this lesson will build upon students' prior understanding of multiplicative comparisons, number line reasoning and equivalent fractions (while highlighting the difference between equivalent fractions and equivalent ratios); and will build toward future work in this unit on building ratio tables, and work in future grades in proportionality, scaling, and expressing and graphing linear functions.