Answer:
Option C is a cubic function
Step-by-step explanation:
Given the options we have to choose the cubic function
Cubic function is the function with degree 3 i.e the highest power of variable is 3.
Option a: [tex]f(x)=3x+1[/tex]
The above polynomial has highest power 1 i.e of degree 1
∴ not a cubic function
Option b: [tex]f(x)=3x^2+x+2[/tex]
The above polynomial has highest power 2 i.e of degree 2
∴ not a cubic function
Option c: [tex]f(x)=5x^3+2x+1[/tex]
The above polynomial has highest power 3 i.e of degree 3
∴ above is a cubic function
Option d: [tex]f(x)=x^3+x^4+5[/tex]
The above polynomial has highest power 4 i.e of degree 4
∴ not a cubic function
