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Find a quadratic polynomial the sum and product of whose zeroes are -3and 2 respectively |
Answer» Answér :x² + x - 6 Note:★ The possible VALUES of the VARIABLE for which the polynomial BECOMES zero are called its zeros . ★ A quadratic polynomial can have atmost two zeros . ★ The general form of a quadratic polynomial is given as ; ax² + bx + c . ★ If α and ß are the zeros of the quadratic polynomial ax² + bx + c , then ; • Sum of zeros , (α + ß) = -b/a • Product of zeros , (αß) = c/a ★ If α and ß are the zeros of a quadratic polynomial , then that quadratic polynomial is given as : k•[ x² - (α + ß)x + αß ] , k ≠ 0. ★ The discriminant , D of the quadratic polynomial ax² + bx + c is given by ; D = b² - 4ac ★ If D = 0 , then the zeros are real and equal . ★ If D > 0 , then the zeros are real and distinct . ★ If D < 0 , then the zeros are unreal (imaginary) . Solution :Here , It is given that , -3 and 2 are the zeros of the required quadratic polynomial . Thus , Let α = -3 and ß = 2 Now , Sum of zeros of the required quadratic polynomial will be ; α + ß = -3 + 2 = -1 ALSO , Product of zeros of the required quadratic polynomial will be ; αß = -3×2 = -6 Thus , The required quadratic polynomial polynomial will be ; => k•[ x² - (α + ß)x + αß ] => k•[ x² - (-1)x + (-6) ] => k•[ x² + x - 6 ] For k = 1 , the polynomial will be ; x² + x - 6 Hence ,Required answer is : x² + x - 6 |
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