Q. Rewrite the function by completing the square.f(x)=x2+2x+26f(x)=(x+□)2+□
Identify coefficient of x: Identify the coefficient of x to complete the square.The coefficient of x is 2. To complete the square, we need to find the value that makes x2+2x a perfect square trinomial.
Calculate value to complete the square: Calculate the value needed to complete the square.We take half of the coefficient of x, which is 22=1, and then square it to get 12=1. This is the value we will add and subtract inside the parentheses to complete the square.
Rewrite the function: Rewrite the function by adding and subtracting the calculated value inside the parentheses.f(x)=x2+2x+1−1+26Now we have added and subtracted 1, which does not change the value of the function, but allows us to complete the square.
Factor and simplify: Factor the perfect square trinomial and simplify the constant terms.f(x)=(x+1)2−1+26f(x)=(x+1)2+25We have factored the trinomial x2+2x+1 into (x+1)2 and combined the constants −1 and 26 to get +25.
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