When x =?, the function f (x) = (x-a1) ^ 2 + (x-a2) ^ 2 +. + (x-an) ^ 2 obtains the minimum value (1,2, n is the subscript) The title doesn't say what a is

When x =?, the function f (x) = (x-a1) ^ 2 + (x-a2) ^ 2 +. + (x-an) ^ 2 obtains the minimum value (1,2, n is the subscript) The title doesn't say what a is

A1, A2 are constants, which are equivalent to 1,2,3. Expand f (x)
nx^2-2(a1+a2+...+an)x+a1^2+a2^2+...an^2
It's a parabola with an opening up, and then the formula comes to the minimum of X on the axis of symmetry
X = (a1 + A2 +... + an) / N is the smallest
I don't know if you understand

The distance on the map is 2.5cm. What is the actual distance? The scale is 1:1600000

2.5 △ 1 / 1600000 = 4000000 cm = 40000 M = 40 km

The distance on the map is 3.2 cm, and the scale is 1:50000. What is the actual distance?

LAN Xiaoyue,
Actual distance: 3.2 × 50000 = 160000 (CM) = 1.6 (km)

On the scale of 1:1000, I want to draw the actual distance of 100m. How many centimeters should I draw on the map

100 △ 1000 = 0.1 M = 10 cm

The scale of a drawing is 30:1, which indicates that the actual distance is a fraction of the distance on the drawing

According to the meaning of scale
1 out of 30