| 1. |
Find K, so that x2 + 2x +K is a factor of 2x4 + x3 – 14x2 + 5x + 6. Also find all thezeros of the two polynomials:(Exempler) |
|
Answer» Given : x² + 2x +K is a FACTOR of 2x⁴ + x³ – 14x² + 5x + 6. To find : all the ZEROS of the two polynomials Solution: 2x² - 3x - (8 + 2K) x² + 2x +K _| 2x⁴ + x³ – 14x² + 5x + 6 |_ 2x⁴ + 4x³+ 2Kx² ________________ -3x³ -(14 +2K)x² + 5x + 6 -3x³ - 6x² -3kx __________________ - (8 + 2K)x² + (5 +3k)x + 6 - (8 + 2K)x² - (16 +4k)x - (8K + 2K²) ___________________________ (21 + 7K)x + (2K² + 8K + 6) x coefficients and constant term must be zero 21 + 7K = 0 => K = - 3 2K² + 8K + 6 = ( K + 3)(2K + 2) Value of K = - 3 as this is common solution x² + 2x +K = x² + 2x - 3 => (x + 3)(x - 1) => Zeroes are -3 , 1 2x² - 3x - (8 + 2K) = 2x² - 3x - 2 = 2x² - 4x + x - 2 = 2x(x - 2) + 1(x - 2) = (2x + 1)(x - 2) => x = -1/2 , 2 Zeroes are - 3 , -1/2 , 1 , 2 Value of k = - 3 Learn More: Obtain all other zeros of x 4 + 4 x cube minus 2 x square - 20 x ... obtain all the zeros of the polynomial 8x^4+8x^3-18x^2-20x-5 if two ... |
|