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Please answer the 24th question. Correct answer will get marked brainliest. |
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Answer» Answer: Required equation is 25x^2 - 30x + 4. Required POLYNOMIAL is 25x^2 - 30x + 4 . Step-by-step explanation: MAY be : Given method is not in your book. ACCORDING to this question : Zeroes of an equation are ( 3 + √5 ) / 5 and ( 3 - √5 ) / 5 . We know, every quadratic equation can be expressed in the form of ( x - a )( x - b ) = 0 , where a and b are the zeroes of that equation. So, if ( 3 + √5 ) / 5 and ( 3 - √5 ) / 5 are zeroes : = > { x - ( 3 + √5 ) / 5 }{ x - ( 3 - √5 ) / 5 } = 0 = > { ( 5x - 3 - √5 ) / 5 }{ ( 5x - 3 + √5 ) / 5 } = 0 = > ( 5x - 3 - √5 )( 5x - 3 + √5 ) = 0 = > 5x( 5x - 3 + √5 ) - 3( 5x - 3 + √5 ) - √5( 5x - 3 + √5 ) = 0 = > 25x^2 - 15X + 5√5 x - 15x + 9 - 3√5 - 5√5 x + 3√5 - 5 = 0 = > 25x^2 - 30x + 4 = 0 Hence the required equation is 25x^2 - 30x + 4 = 0. Method 2 Given zeroes : ( 3 - √5 ) / 5 and ( 3 + √5 ) / 5 . Sum of zeroes : = > ( 3 - √5 ) / 5 + ( 3 + √5 ) / 5 = > ( 3 - √5 + 3 + √5 ) / 5 = > 6 / 5 Product of zeroes : = > ( 3 - √5 ) / 5 = > ( 3 - √5 )( 3 + √5 ) / 25 = > ( 9 - 5 ) / 25 { ( a + b )( a - b ) = a^2 - b^2 } = > 4 / 25 From the properties of quadratic equations : Quadratic equation : x^2 - ( sum of zeroes )x + product of zeroes = 0 = > x^2 - ( 6 / 5 )x + ( 4 / 25 ) = 0 ... { from above } = > ( 25x^2 - 30x + 4 ) / 25 = 0 = > 25x^2 - 30x + 4 = 0 Hence the required equation is 25x^2 - 30x + 4 = 0. And required polynomial is 25x^2 - 30x + 4 . |
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