6. If [tex]\alpha[/tex] and [tex]\beta[/tex] are the zeros of a quadratic polynomial such that [tex]\alpha + \beta = 24[/tex] and [tex]\alpha - \beta = 8[/tex], find a quadratic polynomial having [tex]\alpha[/tex] and [tex]\beta[/tex] as its zeros.



Answer :

Certainly! Let's solve the problem step by step.

Step 1: Given conditions for the roots
We are provided with the following conditions for the roots [tex]\(\alpha\)[/tex] and [tex]\(\beta\)[/tex]:
1. [tex]\(\alpha + \beta = 24\)[/tex]
2. [tex]\(\alpha - \beta = 8\)[/tex]

Step 2: Solve for [tex]\(\alpha\)[/tex] and [tex]\(\beta\)[/tex]
To find the values of [tex]\(\alpha\)[/tex] and [tex]\(\beta\)[/tex], we can use the given conditions:

[tex]\[ \alpha + \beta = 24 \][/tex]
[tex]\[ \alpha - \beta = 8 \][/tex]

We can add these two equations to eliminate [tex]\(\beta\)[/tex]:

[tex]\[ (\alpha + \beta) + (\alpha - \beta) = 24 + 8 \][/tex]
[tex]\[ 2\alpha = 32 \][/tex]
[tex]\[ \alpha = 16 \][/tex]

Next, we substitute [tex]\(\alpha = 16\)[/tex] back into the first equation to find [tex]\(\beta\)[/tex]:

[tex]\[ \alpha + \beta = 24 \][/tex]
[tex]\[ 16 + \beta = 24 \][/tex]
[tex]\[ \beta = 24 - 16 \][/tex]
[tex]\[ \beta = 8 \][/tex]

Now we have [tex]\(\alpha = 16\)[/tex] and [tex]\(\beta = 8\)[/tex].

Step 3: Form the quadratic polynomial
The standard form of a quadratic polynomial with roots [tex]\(\alpha\)[/tex] and [tex]\(\beta\)[/tex] is:

[tex]\[ P(x) = a(x - \alpha)(x - \beta) \][/tex]

Since we typically use [tex]\(a = 1\)[/tex] for the simplest polynomial, it simplifies to:

[tex]\[ P(x) = (x - \alpha)(x - \beta) \][/tex]

Substitute [tex]\(\alpha = 16\)[/tex] and [tex]\(\beta = 8\)[/tex] into the polynomial:

[tex]\[ P(x) = (x - 16)(x - 8) \][/tex]

Step 4: Expand the polynomial
Let's expand the expression:

[tex]\[ P(x) = (x - 16)(x - 8) \][/tex]
[tex]\[ P(x) = x^2 - 8x - 16x + 128 \][/tex]
[tex]\[ P(x) = x^2 - 24x + 128 \][/tex]

Therefore, the quadratic polynomial with roots [tex]\(\alpha = 16\)[/tex] and [tex]\(\beta = 8\)[/tex] is:

[tex]\[ P(x) = x^2 - 24x + 128 \][/tex]

This is the quadratic polynomial having [tex]\(\alpha\)[/tex] and [tex]\(\beta\)[/tex] as its roots.