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    If a = 7 + √2, b = 7 - √2, then what is the value of a² + b²?
    Question

    If a = 7 + √2, b = 7 - √2, then what is the value of a² + b²?

    A.

    104

    B.

    100

    C.

    102

    D.

    98

    Correct option is C

    Given:
    a = 7+27 + \sqrt{2}​​
    b = 727 - \sqrt{2}​​
    Formula Used:
    (a+b)2+(ab)2=2×(a2+b2)(a + b)^2 + (a - b)^2 = 2 × (a^2 + b^2)​​
    Solution:
    We need to find the value of a2+b2.a^2 + b^2.​​
    Substitute the given values into the algebraic identity format directly.
    (7+2)2+(72)2(7 + \sqrt{2})^2 + (7 - \sqrt{2})^2  

    =2×(72+(2)2)= 2 × (7^2 + (\sqrt{2})^2) 

    = 2 ×( 49 + 2) 

    = 2 × 51

    = 102
    Final Answer
    So the correct answer is (c)

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