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If one of the roots of the equation x² - 4 + k = 0 exceeds the other by 2 , then find the roots and determine the value of k.​

User Drstevok
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1 Answer

6 votes

Answer:3

Explanation:

Given

Quadratic equation is
x^2-4+k=0

if one root exceeds the other by two

suppose one of the roots is a, then the other is a+2

The Sum of roots is


=\frac{-\text{coefficient of x}}{\text{coefficient of }x^2}


\therefore a+a+2=-(-0)/(1)\\\\\Rightarrow 2a+2=0\\\Rightarrow a=-1

Product of roots


\Rightarrow (a)(a+2)=(k-4)/(1)\\\Rightarrow (-1)(1)=k-4\\\Rightarrow k=4-1=3

User Neemaximo
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