हिंदी

Form a quadratic equation if the roots of the quadratic equation are 2+7 and 2-7 - Algebra

Advertisements
Advertisements

प्रश्न

Form a quadratic equation if the roots of the quadratic equation are `2 + sqrt(7)` and `2 - sqrt(7)`

योग

उत्तर

Let α = `2 + sqrt(7)` and β = `2 - sqrt(7)`

α + β = `2 + sqrt(7) + 2 - sqrt(7)` = 4

and α × β = `(2 + sqrt(7))(2 - sqrt(7))`

= `(2)^2 - (sqrt(7))^2`    ......[(a + b)(a – b) = a2 – b2]

= 4 – 7

= – 3

∴ The required quadratic equation is

x2 – (α + β)x + αβ = 0

∴ x2 – 4x – 3 = 0

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2: Quadratic Equations - Q.3 (B)

संबंधित प्रश्न

Solve : 7y = -3y2 - 4 


If the roots of x² + kx + k = 0 are real and equal, what is the value of k?


If α and β are the roots of the quadratice equation x²- 2x - 7= 0, find the
value α² + β²


If α and β are the roots of the quadratic equation `x^2 - 4x - 6 = 0`, find  the values of (i) `α^2+β^2` (ii) `α^3+β^3`

 


Form the quadratic equation if the roots are 3 and 8.


Form the quadratic equation if its roots are 5 and 7. 


Solve the quadratic equation : 3x4 - 13x2 +10 = 0.


Choose the correct alternative answer for the following sub-questions and write the correct alphabet.

Which of the following quadratic equation has roots – 3 and – 5?


Choose the correct alternative answer for the following sub questions and write the correct alphabet.

Degree of quadratic equation is always ______


Write the roots of following quadratic equation.

(p – 5) (p + 3) = 0


If one of the roots of quadratic equation x2 – kx – 15 = 0 is – 3, then find the value of ‘k’


Solve the following quadratic equations by formula method.

5m2 – 4m – 2 = 0


Solve the following quadratic equations by formula method.

`y^2 + 1/3y` = 2


Sum of the roots of the quadratic equation is 5 and sum of their cubes is 35, then find the quadratic equation


If the sum of the roots of the quadratic equation x2 + kx + 6 = 0 is 6, then the value of k is ______.


If the roots of the quadratic equation x2 + 12x + a = 0 are real and equal, then find the value of a.


If x = `sqrt(7) - 2`, find the value of `(x + 1/x)`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×