How do you figure out the min or max of a parabola? isnt there some kind of formula?
2007-06-06 15:51:47 · 5 answers · asked by =D 2 in Science & Mathematics ➔ Mathematics
If y = ax^2+bx+c
the x value of a max or min is
2ax+b=0 so x= -b/2a
2007-06-06 15:56:40 · answer #1 · answered by santmann2002 7 · 0⤊ 0⤋
Look at the equation of the parabola in the vertex form, if the valu of a is positive the parabola opens upward and it will give the minimum value of y=k and if the value of a=negative, th constant k will be the maximum.
2007-06-06 23:00:28 · answer #2 · answered by yeshila 1 · 0⤊ 0⤋
You differentiate it.
ie ax^2 becomes 2ax and
bx becoms x.
Equate that to 0 and solve for x.
Then differentiate the differentiated equation again and put the x values in that equation. If the number generated is positive then it is a minimum and if it is negative then it is a maximum.
2007-06-06 22:57:21 · answer #3 · answered by Jahvid S 1 · 0⤊ 0⤋
max is if it is a positive (going up)
min if it is a negative (going down)
for example: -4x^2-6x+3=0 this is min
for example: 4x^2-6x+3=0 this is max
2007-06-06 23:17:32 · answer #4 · answered by ღßutterflyღ 3 · 0⤊ 0⤋
x=-b/2a, and plug back in to find y
or use calculus (which is faster)
(this is a short-cut from calculus)
2007-06-06 22:54:59 · answer #5 · answered by Anonymous · 0⤊ 0⤋