Q. Rewrite the function by completing the square.g(x)=x2−x−6g(x)=□(x+□)2+□
Identify Coefficients: Identify the coefficients of the x2 and x terms in the quadratic function.The coefficient of x2 is 1, and the coefficient of x is −1. We will use these to complete the square.
Divide and Square: Divide the coefficient of the x term by 2 and square the result to find the number to complete the square.The coefficient of x is −1, so we divide it by 2 to get −21, and then square (−21) to get 41.
Add and Subtract: Add and subtract the squared number inside the function to complete the square.We add and subtract (1/4) inside the function to maintain the equality.g(x)=x2−x+(1/4)−(1/4)−6
Rewrite as Perfect Square: Rewrite the quadratic part of the function as a perfect square.The quadratic part of the function is now x2−x+41, which can be written as (x−21)2 because (x−21)(x−21)=x2−x+41.g(x)=(x−21)2−41−6
Combine Constants: Combine the constants outside the perfect square.Combine −41 and −6 to get −6−41=−424−41=−425.g(x)=(x−21)2−425
Final Form: Write the final form of the function by completing the square.The completed square form of the function is g(x)=(x−21)2−425.
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