Question

Which is a cubic function? a. f(x) = 3x + 1 b. f(x) = 3x2 + x + 2 c. f(x) = 5x3 + 2x + 1 d. f(x) = x3 + x4 + 5

Answer 1

A cubic function is a function with the highest degree of 3. So the answer is V

Answer 2

Option C is a cubic function

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:
`f(x)=3x+1`

The above polynomial has highest power 1 i.e of degree 1

∴ not a cubic function

Option b:
`f(x)=3x^2+x+2`

The above polynomial has highest power 2 i.e of degree 2

∴ not a cubic function

Option c:
`f(x)=5x^3+2x+1`

The above polynomial has highest power 3 i.e of degree 3

∴ above is a cubic function

Option d:
`f(x)=x^3+x^4+5`

The above polynomial has highest power 4 i.e of degree 4

∴ not a cubic function