Question

Which function is a quadratic function? c(x) = 6x + 3x3 d(x) = x – 8x4 p(x) = –5x – x2 k(x) = 2x2 + 9x4

Answer 1

quadratic means 2nd degree

means highest power of variable is 2


c(x)=6x+3x^3
3rd degree, not quadratic

d(x)=x-8x^4,
4th degree, not quadratic

p(x)=-5x-x^2
2nd degree, it's quadratic

k(x)=2x^2+9x^4
4th degree, not quadratic

answer is p(x)= -5x- x^2