Explore Westonci.ca, the leading Q&A site where experts provide accurate and helpful answers to all your questions. Explore a wealth of knowledge from professionals across different disciplines on our comprehensive platform. Explore comprehensive solutions to your questions from a wide range of professionals on our user-friendly platform.
Sagot :
To construct a quadratic equation given its roots, we need to use the fact that for a quadratic equation of the form [tex]\( ax^2 + bx + c = 0 \)[/tex], if [tex]\(\alpha\)[/tex] and [tex]\(\beta\)[/tex] are the roots, then:
1. The sum of the roots, [tex]\(\alpha + \beta = -\frac{b}{a}\)[/tex]
2. The product of the roots, [tex]\(\alpha \beta = \frac{c}{a}\)[/tex]
Given the roots [tex]\(\frac{4}{5}\)[/tex] and [tex]\(-2 \frac{2}{3}\)[/tex], we first convert these numbers to a common fraction form:
- [tex]\(\frac{4}{5}\)[/tex] is already in fraction form.
- [tex]\(-2 \frac{2}{3}\)[/tex] can be converted to an improper fraction:
[tex]\[ -2 \frac{2}{3} = -\left(2 + \frac{2}{3}\right) = -\left(\frac{6}{3} + \frac{2}{3}\right) = -\frac{8}{3} \][/tex]
Now, let's denote the roots as:
[tex]\[ \alpha = \frac{4}{5}, \quad \beta = -\frac{8}{3} \][/tex]
Step 1: Calculate the sum of the roots.
Sum of the roots [tex]\(\alpha + \beta\)[/tex] is:
[tex]\[ \alpha + \beta = \frac{4}{5} + \left( -\frac{8}{3} \right) \][/tex]
To add these fractions, we need a common denominator. The least common multiple of 5 and 3 is 15. Converting both fractions to have this common denominator:
[tex]\[ \frac{4}{5} = \frac{4 \times 3}{5 \times 3} = \frac{12}{15}, \quad -\frac{8}{3} = \frac{-8 \times 5}{3 \times 5} = \frac{-40}{15} \][/tex]
Now we can add them:
[tex]\[ \frac{12}{15} + \frac{-40}{15} = \frac{12 - 40}{15} = \frac{-28}{15} \][/tex]
Step 2: Calculate the product of the roots.
Product of the roots [tex]\(\alpha \beta\)[/tex] is:
[tex]\[ \alpha \beta = \left(\frac{4}{5}\right) \left(-\frac{8}{3}\right) \][/tex]
Multiplying the fractions:
[tex]\[ \left(\frac{4}{5}\right) \left(-\frac{8}{3}\right) = \frac{4 \times (-8)}{5 \times 3} = \frac{-32}{15} \][/tex]
Step 3: Write the quadratic equation using the sum and product of the roots.
In general, the quadratic equation based on the sum and product of the roots is given by:
[tex]\[ x^2 - (\text{sum of roots})x + (\text{product of roots}) = 0 \][/tex]
Plugging in our values:
[tex]\[ x^2 - \left(\frac{-28}{15}\right)x + \left(\frac{-32}{15}\right) = 0 \][/tex]
Simplifying the signs:
[tex]\[ x^2 + \frac{28}{15}x - \frac{32}{15} = 0 \][/tex]
Thus, the quadratic equation whose roots are [tex]\(\frac{4}{5}\)[/tex] and [tex]\(-2\frac{2}{3}\)[/tex] is:
[tex]\[ x^2 + \frac{28}{15}x - \frac{32}{15} = 0 \][/tex]
1. The sum of the roots, [tex]\(\alpha + \beta = -\frac{b}{a}\)[/tex]
2. The product of the roots, [tex]\(\alpha \beta = \frac{c}{a}\)[/tex]
Given the roots [tex]\(\frac{4}{5}\)[/tex] and [tex]\(-2 \frac{2}{3}\)[/tex], we first convert these numbers to a common fraction form:
- [tex]\(\frac{4}{5}\)[/tex] is already in fraction form.
- [tex]\(-2 \frac{2}{3}\)[/tex] can be converted to an improper fraction:
[tex]\[ -2 \frac{2}{3} = -\left(2 + \frac{2}{3}\right) = -\left(\frac{6}{3} + \frac{2}{3}\right) = -\frac{8}{3} \][/tex]
Now, let's denote the roots as:
[tex]\[ \alpha = \frac{4}{5}, \quad \beta = -\frac{8}{3} \][/tex]
Step 1: Calculate the sum of the roots.
Sum of the roots [tex]\(\alpha + \beta\)[/tex] is:
[tex]\[ \alpha + \beta = \frac{4}{5} + \left( -\frac{8}{3} \right) \][/tex]
To add these fractions, we need a common denominator. The least common multiple of 5 and 3 is 15. Converting both fractions to have this common denominator:
[tex]\[ \frac{4}{5} = \frac{4 \times 3}{5 \times 3} = \frac{12}{15}, \quad -\frac{8}{3} = \frac{-8 \times 5}{3 \times 5} = \frac{-40}{15} \][/tex]
Now we can add them:
[tex]\[ \frac{12}{15} + \frac{-40}{15} = \frac{12 - 40}{15} = \frac{-28}{15} \][/tex]
Step 2: Calculate the product of the roots.
Product of the roots [tex]\(\alpha \beta\)[/tex] is:
[tex]\[ \alpha \beta = \left(\frac{4}{5}\right) \left(-\frac{8}{3}\right) \][/tex]
Multiplying the fractions:
[tex]\[ \left(\frac{4}{5}\right) \left(-\frac{8}{3}\right) = \frac{4 \times (-8)}{5 \times 3} = \frac{-32}{15} \][/tex]
Step 3: Write the quadratic equation using the sum and product of the roots.
In general, the quadratic equation based on the sum and product of the roots is given by:
[tex]\[ x^2 - (\text{sum of roots})x + (\text{product of roots}) = 0 \][/tex]
Plugging in our values:
[tex]\[ x^2 - \left(\frac{-28}{15}\right)x + \left(\frac{-32}{15}\right) = 0 \][/tex]
Simplifying the signs:
[tex]\[ x^2 + \frac{28}{15}x - \frac{32}{15} = 0 \][/tex]
Thus, the quadratic equation whose roots are [tex]\(\frac{4}{5}\)[/tex] and [tex]\(-2\frac{2}{3}\)[/tex] is:
[tex]\[ x^2 + \frac{28}{15}x - \frac{32}{15} = 0 \][/tex]
Thank you for your visit. We are dedicated to helping you find the information you need, whenever you need it. Thank you for choosing our platform. We're dedicated to providing the best answers for all your questions. Visit us again. Thank you for choosing Westonci.ca as your information source. We look forward to your next visit.