Answer:
Step-by-step explanation:
hello
so to know the maximum to y we can check the maximum of
f(x)=
f is derivable and f'(x)=6-2x
f'(x)=0 <=> x = 3
so the maximum is reached for x = 3
f(3)=18-9=9
and then
to be rigorous, we can write the variation table of y to show that there is only one maximum
hope this helps