Q. The function f is defined as f(x)=2x+3.What is the x-coordinate of the point on the function's graph that is closest to the origin?
Define Distance Formula: To find the point closest to the origin, we need to minimize the distance from the point (x,f(x)) to the origin (0,0). The distance formula is D=((x−0)2+(f(x)−0)2).
Substitute f(x): Substitute f(x) with 2x+3 to get the distance in terms of x: D=x2+(2x+3)2.
Simplify Distance Formula: Now we have D=x2+(4x2+12x+9), which simplifies to D=5x2+12x+9.
Minimize Distance: To find the minimum distance, we can take the derivative of D with respect to x and set it to zero. But since D is always positive, we can minimize D2 for simplicity. So we'll minimize 5x2+12x+9.
Find Derivative: The derivative of 5x2+12x+9 with respect to x is 10x+12.
Set Derivative Equal: Set the derivative equal to zero to find the critical point: 10x+12=0.