Show that x^2 - x +2 is positive for all values of x

(x-1/2)= (x-1/2)(x-1/2)=x2-x+1/4, add 7/4 to get x2-x+2 therefore x2-x+2 = (x-1/2)2 + 7/4

squared numbers always positive so (x-1/2)2 >= 0 therefore (x-1/2)2 + 7/4 is always positive

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Answered by Pearse M. Maths tutor

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