Home
Class 12
MATHS
Form the polynomial equation whose r...

Form the polynomial equation whose root are
`1,3-sqrt(-2)`

Text Solution

AI Generated Solution

The correct Answer is:
To form the polynomial equation whose roots are \(1\) and \(3 - \sqrt{-2}\), we will follow these steps: ### Step 1: Identify the roots The roots given are: - \( \alpha = 1 \) - \( \beta = 3 - \sqrt{-2} = 3 - i\sqrt{2} \) ### Step 2: Write the polynomial in factored form The polynomial can be expressed in factored form as: \[ (x - \alpha)(x - \beta) = 0 \] Substituting the values of \(\alpha\) and \(\beta\): \[ (x - 1)(x - (3 - i\sqrt{2})) = 0 \] ### Step 3: Expand the polynomial Now, we will expand the expression: \[ (x - 1)(x - (3 - i\sqrt{2})) = (x - 1)(x - 3 + i\sqrt{2}) \] Using the distributive property (FOIL method): \[ = x(x - 3 + i\sqrt{2}) - 1(x - 3 + i\sqrt{2}) \] \[ = x^2 - 3x + i\sqrt{2}x - x + 3 - i\sqrt{2} \] \[ = x^2 - 4x + 3 + i\sqrt{2}x - i\sqrt{2} \] ### Step 4: Combine like terms Now, we combine the real and imaginary parts: \[ = x^2 - 4x + (3 - i\sqrt{2}) + i\sqrt{2}x \] Since we want a polynomial with real coefficients, we need to consider the conjugate of the root \(3 - i\sqrt{2}\), which is \(3 + i\sqrt{2}\). Thus, we will also include this root. ### Step 5: Form the complete polynomial Now we will form the polynomial with both roots \(1\) and \(3 \pm i\sqrt{2}\): \[ (x - 1)((x - 3) + i\sqrt{2})((x - 3) - i\sqrt{2}) = 0 \] The product of the conjugate pair can be simplified: \[ (x - 3)^2 + 2 = 0 \] Thus, the polynomial becomes: \[ (x - 1)((x - 3)^2 + 2) = 0 \] ### Step 6: Expand the final polynomial Now we expand this: \[ = (x - 1)(x^2 - 6x + 9 + 2) \] \[ = (x - 1)(x^2 - 6x + 11) \] Now we expand: \[ = x(x^2 - 6x + 11) - 1(x^2 - 6x + 11) \] \[ = x^3 - 6x^2 + 11x - x^2 + 6x - 11 \] \[ = x^3 - 7x^2 + 17x - 11 \] ### Final Polynomial Thus, the polynomial equation whose roots are \(1\) and \(3 - \sqrt{-2}\) is: \[ x^3 - 7x^2 + 17x - 11 = 0 \]
Promotional Banner

Similar Questions

Explore conceptually related problems

Form the polynomial equation whose root are 2 ,1 +- 3i

From the polynomial equation whose roots are 3,2,1+i,1-i

Form the polynomial equation whose root are 4+- sqrt(3) ,2 +- i

From the polynomial equation whose roots are 1+I,1-I,1+I,1-I

Form the polynomial equation of degree 3 whose roots are 2,3 and 6.

The equation whose roots are 1,2 +- 3i is

Find the polynomial equation whose roots are the translates of the roots of the equation . x^4-x^3-10x^2+4x+24=0 by 2 .

Find the polynomial equation whose roots are the negatives of the roots of the equation x^4 -6x +7x^2 -2x +1=0

Form the polynomial with rational coefficients whose roots are i+- sqrt(5)

Form the polynomial with rational coefficients whose roots are 5+-2i