Express x^2-7x+2 in the form (x-p)^2+q where p and q are rational. Hence or otherwise find the minimum value of x^2-7x+2
For the first part, use the 'complete the square method', which gives (x-7/2)2 -49/4+2, simplified to (x-7/2)2-41/4. To find the answer for the second part, set x=7/2 so that the bracketed part becomes 0, meaning the minimum value is 41/4
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