Question 1096819
P(0) is 0.
P(3)=3^3-18(3^2)+81(3)=27-162+243=108.  This is a cubic equation, and the first term is cubed.
P(5)=5^3-18(25)+81(5)=125-450+405=80
P(10)=10^3-18(100)+81(10)=1000-1800+810=10.
Check P(9)=9^3-18(81)+81(9)=729-1458+729=0
The drop is from P(3) to P(9), and the graph shows that as well.
{{{graph(300,300,-10,15,-50,200,x^3-18x^2+81x)}}}