Q. Find the minimum value of the function f(x)=0.4x2+x+5 to the nearest hundredth.Answer:
Calculate Vertex: To find the minimum value of the quadratic function f(x)=0.4x2+x+5, we can use the vertex formula for a parabola. The vertex of a parabola given by f(x)=ax2+bx+c is at the point (h,k), where h=−2ab and k is the value of the function at x=h.
Find x-coordinate: First, we calculate the x-coordinate of the vertex, h, using the formula h=−b/(2a). In our function, a=0.4 and b=1, so h=−1/(2×0.4)=−1/0.8=−1.25.
Find y-coordinate: Next, we calculate the y-coordinate of the vertex, k, by substituting x=h into the function. So we evaluate f(−1.25)=0.4(−1.25)2+(−1.25)+5.
Evaluate f(−1.25): Calculating f(−1.25) gives us 0.4(1.5625)−1.25+5=0.625−1.25+5=4.375.
Determine Parabola Direction: Since the coefficient of x2 is positive (a = 0.4 > 0), the parabola opens upwards, and the vertex represents the minimum point of the function.
Calculate Minimum Value: Therefore, the minimum value of the function f(x) is 4.375, and since we need to round to the nearest hundredth, the minimum value is 4.38.
More problems from Find trigonometric functions using a calculator