The first thing we have to see is that exercise (c) is given as follows
![(c)_{}\to(-4)/(f(k))](https://img.qammunity.org/2023/formulas/mathematics/college/kn3tbdsjplaxx6yiw6kaep5nzrajtoa2c1.png)
From (e) we know:
![f(k)=-4k+7](https://img.qammunity.org/2023/formulas/mathematics/college/w5ihybdhddk7jro9ww32rir7pgqaba78uu.png)
So we replace f(k) of the (e) part on the (c) part as follows:
![f(k)=(-4)/((-4k+7))](https://img.qammunity.org/2023/formulas/mathematics/college/67bbc81gr04kysjqzcsguydbh58mjh7bdv.png)
Now we must find the value of x the function F (k) is not defined. This value is given when the denominator of the function gives 0 since the function would be indeterminate then:
![\begin{gathered} -4k+7=0 \\ -4k=-7 \\ k=(7)/(4) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/m655dxjsp75pda46hngwutrdbh0xzqfs62.png)
The domain of this function is indeterminate for k = 7/4 and this value is the one that must be excluded from the domain
All functions have a domain and a range. The domain of a function is all the values that the function can take along the k-axis and the range on the f(k)-axis.