Polynomials

Question

Should i write a4-7a²b²+kb4 in f(a) or f(b)?

because i am confused and it has 2 variables in this polynomial.

Answer 1

Since f depends on both a and b, the correct notation is f(a,b).

Answer 2

If a and b are both independent variables, then it is f(a,b), a function of 2 variables.

 

f(a,b) = a⁴-7a²b²+kb⁴

 

Multi-variable functions are actually quite common in the real world.

Answer 3

Depends on the context. It could be f(a), f(b), or even f(a,b).

 

What's in the parentheses is the variable(s), the other letters are coefficients.