हिंदी

Find All the Zeroes of Polynomial `(2x^4 – 11x^3 + 7x^2 + 13x – 7)`, It Being Given that Two of Its Zeroes Are `(3 + Sqrt2) and (3 – Sqrt2)`. - Mathematics

Advertisements
Advertisements

प्रश्न

Find all the zeroes of polynomial `(2x^4 – 11x^3 + 7x^2 + 13x – 7)`, it being given that two of its zeroes are `(3 + sqrt2) and (3 – sqrt2)`. 

 

Advertisements

उत्तर

The given polynomial is f(x) = `2x^4 – 11x^3 + 7x^2 + 13x – 7.`
Since `(3 + sqrt2) and (3 – sqrt2)` are the zeroes of f(x) it follows that each one of `(x + 3 + sqrt2) and (x + 3 – sqrt2) `is a factor of f(x).
Consequently,` [(x – ( 3 + sqrt2)] [(x – (3 – sqrt2)] = [(x – 3) - sqrt2 ] [(x – 3) + sqrt2 ]`
=`[(x – 3)^2 – 2 ] = x^2 – 6x + 7,` which is a factor of f(x).  

On dividing f(x) by `(x^2 – 6x + 7)`, we get: 

 

                            

f(x) = 0
⇒` 2x^4 – 11x^3 + 7x^2 + 13x – 7 = 0`
⇒ `(x^2 – 6x + 7) (2x2 + x – 7) = 0`
⇒` (x + 3 + sqrt2) (x + 3 – sqrt2) (2x – 1) (x + 1) = 0`
⇒ `x = –3 – sqrt2 or x = –3 + sqrt2 or x =1/2 or x = -1`
Hence, all the zeroes are `(–3 – sqrt2), (–3 + sqrt2),1/2 and -1.` 

 

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2: Polynomials - Exercises 2

APPEARS IN

आर.एस. अग्रवाल Mathematics [English] Class 10
अध्याय 2 Polynomials
Exercises 2 | Q 19

संबंधित प्रश्न

The graphs of y = p(x) are given in following figure, for some polynomials p(x). Find the number of zeroes of p(x).


Find the zeroes of the quadratic polynomial `f(x) = 5x^2 ˗ 4 ˗ 8x` and verify the relationship between the zeroes and coefficients of the given polynomial.


One zero of the polynomial `3x^3+16x^2 +15x-18 is 2/3` . Find the other zeros of the  polynomial.


If f(x) =`x^3-3x+5x-3` is divided by g(x)=`x^2-2` 

 


If one zero of the polynomial `x^2-4x+1 is (2+sqrt3)` , write the other zero. 


If the sum of the zeros of the quadratic polynomial `kx^2-3x + 5` is 1 write the value of k.. 

 

 


Find the sum of the zeros and the product of zeros of a quadratic polynomial, are `−1/2` and \ -3 respectively. Write the polynomial. 


If ∝ and β are the zeros of the polynomial f(x) = `6x^2 + x - 2 `find the value of `(∝/β+∝/β) ` 

 


Find the value of k such that the polynomial  x2-(k +6)x+ 2(2k - 1) has some of its zeros equal to half of their product.


Find the value of k such that the polynomial x2 − (k + 6)x + 2(2k −1) has sum of its zeros equal to half of their product.


If one zero of the quadratic polynomial x2 + 3x + k is 2, then the value of k is ______.


If the zeroes of the quadratic polynomial x2 + (a + 1) x + b are 2 and –3, then ______.


Consider the following statements.

  1. x – 2 is a factor of x3 – 3x² + 4x – 4.
  2. x + 1 is a factor of 2x3 + 4x + 6.
  3. x – 1 is a factor of x5 + x4 – x3 + x² -x + 1.

In these statements


If 4x² – 6x – m is divisible by x – 3, the value of m is exact divisor of ______.


The number of polynomials having zeroes as -2 and 5 is ______.


If the graph of a polynomial intersects the x-axis at only one point, it cannot be a quadratic polynomial.


The zeroes of the quadratic polynomial x2 + kx + k, k ≠ 0 ______.


If α and β are the zeroes of the polynomial x2 – 1, then the value of (α + β) is ______.


The zeroes of the quadratic polynomial 16x2 – 9 are ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×