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How To Find Maximum And Minimum Values Of Quadratic Functions?

In order to depict the minimum and maximum definition, it can be mentioned that the leading coefficient of the quadratic functions or standard quadratic equations is also determined as the sign of “a”. For example, if in the function: “f(x) = ax2 + bx + c”, the sign of “a” gives a negative value then the leading coefficient will deliver the maximum value in the quadratic equations. When the parabola of the vertex opens down there is no minimum value derived from the graph. In the minimum value of quadratic equations, in the fractions: “f(x) = ax2 + bx + c”, if the sign “a” gives a positive value then its leading coefficient will always deliver the minimum value. 

Quadratic function: discussion

In order to find the minimum and maximum value, it is important to clear up the concept of quadratic functions which are mainly defined by quadratic expressions. This quadratic expression can be written in a specific form that is “f(x) = ax2 + bx +c”. The quadratic function degree always remains the same, that is “2”. The parabola vertex is considered in the graph to derive the minimum and maximum definition of the quadratic equations or functions. In this functional graph “a” is determined as the leading coefficient if the vertex parabola opens down or opens up. 

The maximum and minimum definition

In order to state the minimum and maximum definition, it is necessary to have a clear concept of quadratic functions or standard quadratic equations. In order to find a range of quadratic equations, it is important to determine the vertex parabola of the given equation and after that only it can be determined whether the parabola opens down or up. The quadratic form vertex can be obtained by applying the formula, “x=−b2a”. The range of quadratic functions can be derived by calculating the quadratic equation, with the help of a specific formula that is “f(x)=ax2+bx+c”. To further elaborate on the minimum and maximum definition it can be stated that, on the opening of the parabola upwards, the vertex is “h, k”, and is considered the lowest or minimal point on the parabola, in the quadratic equations. Here “k” is identified as the minimum value of the fraction “f”. 

The maximum value

To determine the maximum value, it can be explained that if the parabola of the quadratic equations opens down, then “k” will be considered as the maximum value of the fraction “f”. It can also be determined as the absolute form of the maximum value of the fraction “f” which occurs in “x=h”. 

The minimum and maximum value

In quadratic equations, extreme functional values are often referred to as the minimum and maximum values of given quadratic equations. Both the minimum and maximum values are considered as vertices of parabolas having coordinates “k, k”, where “h= (– b)2a and k = f (h)”. In order to derive the correct minimum and maximum definition of quadratic equations or the standard quadratic functions, three main forms of quadratic equations are used such as the standard form is [f(x)=ax2+bx+c], vertex form is [f(x)=a(x−h)2+k], and the factored form is [f(x)= a(x−b)(x−c)]. 

Conclusion 

In the quadratic equations, where the function range of “y” is equal to f(x), is determined as the set of the “y” values for all values of “x” present in the domain “f”. By using the quadratic graph and form “f(x) = a x2 + b x + c”, the vertex form can be provided as “f(x) = a(x – h) 2 + k, where h = – b/2a and k = f (h)”. This denotes that the vertex parabola either opens up when “a” is greater than 0 or opens down when “a” is less than 0. Hence, if “a” is greater than 0, then the graph “f” will have a minimum point but if “a” is less than 0, the graph “f” will have the maximum point.

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