The given function has a single extreme value, namely a
minimum value (bcause the coefficient of x^2 is positive). The minimum value is
represented by the vertex of the parable, whose expression is 10x^2 - 2x +
5.
The coordinates of the vertex are: V(xV ,
yV):
xV = -b/2a
yV =
-delta/4a
delta = b^2 -
4ac
We'll identify the coefficients
a,b,c:
a = 10
b =
-2
c = 5
Now, we'll determine
the coordinates of the vertex:
xV =
-(-2)/2*10
xV =
1/10
xV =
0.1
yV = -(4 -
200)/4*10
yV = 196/4*10
yV =
49/10
yV =
4.9
The function has just one
extreme point and it's coordinates are: (0.1 ,
4.9).
Another manner to verify
the existence and the number of extreme points of a function is to differentiate the
function.
We'll differentiate
f(x).
f'(x) = (10x^2 - 2x +
5)'
f'(x) = 20x - 2
We'll
calculate the roots of f'(x):
f'(x) =
0
20x - 2 = 0
We'll divide by
2:
10x - 1 = 0
x =
1/10
The function has an extreme point for any root of the
derivative.
Since the derivative has just one root, the
function will have just a single extreme point.
f(1/10) =
10/100 - 2/10 + 5
f(1/10) = 1/10 - 2/10 +
5
f(1/10) = -1/10 + 5
f(1/10)
= (-1+50)/10
f(1/10) = 49/10
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