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If a1,a2,a3,......an ∈R,a_1,a_2,a_3,......a_n\space ∈ R,a1​,a2​,a3​,......an​ ∈R,​, then (x−a1)2+(x−a2)2+.......+(x−an)2=0(x-a_1)^2+(x-
Question

If a1,a2,a3,......an R,a_1,a_2,a_3,......a_n\space ∈ R,​, then (xa1)2+(xa2)2+.......+(xan)2=0(x-a_1)^2+(x-a_2)^2+.......+(x-a_n)^2=0​ assumes its least value at:

A.

x=(a1+a2+a3+...+an)nx=\frac{(a_1+a_2+a_3+...+a_n)}{n}​​

B.

x=2(a1+a2+a3+...+an)x=2(a_1+a_2+a_3+...+a_n)​​

C.

x=n(a1+a2+a3+...an)x=n(a_1+a_2+a_3+...a_n)​​

D.

x=2(a1+a2+a3+...+an)nx=\frac{2(a_1+a_2+a_3+...+a_n)}{n}​​

Correct option is A

Solution:

To find the value of  x  that minimizes the function:

(x - a₁)² + (x - a₂)² + ...... + (x - aₙ)²
The given function represents the sum of squared deviations from a set of real numbers a₁, a₂, ..., aₙ.
This type of function is minimized when x is the mean (average) of the given values.

The function
f(x) = Σ (x - aᵢ)² for i = 1 to n
is minimized when x is the mean of the given values, which is:
x=(a1+a2+...+an)nx =\frac{ (a₁ + a₂ + ... + aₙ) }{ n}​​

Thus, the given function assumes its least value at:
x=(a1+a2+...+an)nx =\frac{ (a₁ + a₂ + ... + aₙ) }{ n}​​

which is the arithmetic mean of a₁, a₂, ..., aₙ.

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