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Please help I need to clarify if the questions are correct I don't really know the domain though

Please help I need to clarify if the questions are correct I don't really know the-example-1
User Alexander Kachkaev
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1 Answer

11 votes
11 votes

Domain\text{ of goh: (-}\infty,\text{ 2) }\cup\text{ (2, }\infty)

Step-by-step explanation:

(g o h)(x): inserting the values of h(x) into g(x)

g(x) = (x + 6)/(x+ 5)

h(x) = 2x - 9


\begin{gathered} \mleft(goh\mright)\mleft(x\mright)=\frac{(2x\text{ -9)+6}}{(2x\text{ -9)+5}} \\ =\text{ }\frac{2x\text{ -9+6}}{2x\text{ -9+5}} \\ (goh)(x)=(2x-3)/(2x-4) \end{gathered}

To get the domain of (g o h)(x) = (2x - 3)/(2x -4)

if the value of x = 2

(g o h)(x) = (2x - 3)/(2(2) -4) = (2(2)- 3)/(4-4)

= (4-3)/0 = undefined

This means the domain of x is from negative infinty to number before 2. And from number after 2 to positive infinity. 2 makes it undefined.

In interval notation:

Since 2 is not inclusive, it would have ) instead of ]


Domain\text{ of goh: (-}\infty,\text{ 2) }\cup\text{ (2, }\infty)

User Vasion
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