Tuesday, June 5, 2012

What is the extreme value of y= 3x^2 -3x +5, Is is max. or min?

Given the equation:


y= 3x^2 -
3x + 5


We need to find the extreme
value.


First we need to determine the first
derivative.


==> y' = 6x
-3


Now we will calculate the critical
value.


==> 6x -3 = 0  ==> x =
1/2


Now we will determine the values of
y(1/2)


==> y(1/2) = 3(1/4) - 3(1/2) + 5 = 3/4 - 3/2
+ 5 = ( 3 - 6 + 20)/4 = 17/4


==> y(1/2) =
17/4


Since the coefficient of x^2 is positive, then the
parabola is facing up.


Then the parabola has a minimum
point at x= 1/2.


Then the extreme values for
y is the point ( 1/2, 17/4) and it is a minimum.

No comments:

Post a Comment

Calculate tan(x-y), if sin x=1/2 and sin y=1/3. 0

We'll write the formula of the tangent of difference of 2 angles. tan (x-y) = (tan x - tan y)/(1 + tan x*tan y) ...