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If the sum of two positive real numbers is 1 then what is the minimum value of the sum of their squares?
    Correct answer is '0.5'. Can you explain this answer?
    Verified Answer
    If the sum of two positive real numbers is 1 then what is the minimum ...
    Let the two numbers be a and b.
    a + b = 1
    Maximum value of ab will occur at a = b = 0.5
    And the maximum value of ab = 0.5 x 0.5 = 0.25
    Maximum value of 2ab = 2 * 0.25 = 0.5
    Now, (a + b)2 = 1
    a2 + b2 + 2ab = 1
    a2 + b2 = 1 - 2ab
    a2 + b2 will be minimum when 2ab will be maximum i.e. 0.5.
    Minimum value of a2 + b2 = 0.5
    Answer: 0.5
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    Most Upvoted Answer
    If the sum of two positive real numbers is 1 then what is the minimum ...
    The minimum value of the sum of the squares of two positive real numbers can be found using the concept of optimization.

    Problem:
    Let's assume we have two positive real numbers, x and y, with the sum of 1. We need to find the minimum value of the sum of their squares, x^2 + y^2.

    Approach:
    To solve this problem, we can use the concept of optimization by considering the given condition and trying to minimize the sum of squares.

    Step 1: Formulating the problem mathematically
    Let's formulate the problem mathematically:
    We need to minimize f(x, y) = x^2 + y^2, given the constraint x + y = 1.

    Step 2: Solving the problem
    We can solve this problem using the method of Lagrange multipliers, which helps us find the minimum or maximum of a function subject to constraints.

    Step 2.1: Formulating the Lagrangian function
    The Lagrangian function is given by:
    L(x, y, λ) = f(x, y) - λ(g(x, y)), where g(x, y) represents the constraint equation and λ is the Lagrange multiplier.

    In our case, the Lagrangian function becomes:
    L(x, y, λ) = x^2 + y^2 - λ(x + y - 1)

    Step 2.2: Finding the partial derivatives
    Next, we find the partial derivatives of the Lagrangian function with respect to x, y, and λ:
    ∂L/∂x = 2x - λ
    ∂L/∂y = 2y - λ
    ∂L/∂λ = -(x + y - 1)

    Step 2.3: Setting the partial derivatives to zero
    To find the critical points, we set the partial derivatives to zero:
    2x - λ = 0
    2y - λ = 0
    -(x + y - 1) = 0

    Solving these equations simultaneously, we get:
    x = y = 1/2
    λ = 2

    Step 2.4: Checking the nature of the critical point
    To determine if the critical point is a minimum, maximum, or a saddle point, we need to analyze the second-order partial derivatives. However, in this case, we can observe that the function x^2 + y^2 is always positive or zero. Therefore, the minimum value of x^2 + y^2 occurs when x = y = 1/2.

    Step 3: Substituting the values back
    Substituting x = y = 1/2 in the function f(x, y) = x^2 + y^2, we get:
    f(1/2, 1/2) = (1/2)^2 + (1/2)^2 = 1/4 + 1/4 = 1/2

    Hence, the minimum value of the sum of the squares of two positive real numbers, given their sum is 1, is 1/2 or 0.5.
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    If the sum of two positive real numbers is 1 then what is the minimum value of the sum of their squares?Correct answer is '0.5'. Can you explain this answer?
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