the maximum value of y = 3 +2x + x²

the maximum value is get from y' = 0.
y = 3 +2x + x^2
y' = 2 + 2x
2+ 2x = 0
2x = -2
x = -2/2
x = -1. subsitute x = -1 to funcion, so
y = 3 + 2(-1) + (-1)^2
y = 3 -2 + 1
y = 2
so maximum value function is 2.

Xp = -b/2a
= -2/2.1
= -2/2
= -1

Yp= b^2-4ac/-4a
= 2^2-4.1.3/-4.1
= 4-12/-4
= -8/-4
= 2


(Xp,Yp)
(-1,2)