Q. The function f is defined as f(x)=29−x.What is the x-coordinate of the point on the function's graph that is closest to the origin?
Define Function: The function is f(x)=29−x. To find the x-coordinate of the point closest to the origin, we need to minimize the distance from the origin to the point on the graph.
Distance Formula: The distance from the origin to any point (x,f(x)) on the graph is given by the distance formula: D=x2+f(x)2.
Substitute and Simplify: Substitute f(x) into the distance formula: D=x2+(29−x)2.
Minimize Distance: Simplify the distance formula: D=x2+4(9−x).
Expand Expression: To minimize D, we need to minimize the expression under the square root since the square root function is increasing. So we minimize x2+4(9−x).
Complete the Square: Expand the expression: x2+4(9−x)=x2+36−4x.To find the minimum, we can complete the square or take the derivative and set it to zero. Since we're looking for a simple solution, let's complete the square.
Complete the Square: Expand the expression: x2+4(9−x)=x2+36−4x.To find the minimum, we can complete the square or take the derivative and set it to zero. Since we're looking for a simple solution, let's complete the square.Rewrite the expression as a perfect square: x2−4x+36=(x−2)2+32.
More problems from Rational functions: asymptotes and excluded values