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    Answers are 1 and -1 but how?
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    (Original post by Jyashi)
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    Answers are 1 and -1 but how?
    differentiate and set equal to zero
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    (Original post by Jyashi)
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    Answers are 1 and -1 but how?
    y=x + x^-1
    dy/dx = 1 - x^-2=0
    1=1/x^2
    x^2 = 1
    x = 1 or -1
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    The tangent being parallel to the x-axis means the gradient is zero.
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    Thanks guys it makes sense now. Ofcourse, why didnt i think that tangent being parallel to x means its either a min or max point and therefore gradient is 0
 
 
 
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