Question 1184513
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{{{2x^2 + x - 3}}}

Factor 2 out of the first two terms

{{{2(x^2+expr(1/2)x)-3}}}

To the side take half of the coefficient of x, which is 1/2 of 1/2 or 1/4.
Square it. Get (1/4)<sup>2</sup>=1/16.
Add and subtract 1/16 inside the parentheses (which amounts to adding zero)

{{{2(x^2+expr(1/2)x+1/16-1/16)-3}}}

Factor the first three terms inside the parentheses

{{{2((x+1/4)(x+1/4)^""-1/16)-3}}}

{{{2((x+1/4)^2-1/16)-3}}}

Distribute the 2:

{{{2(x+1/4)^2-1/8-3}}}

{{{2(x+1/4)^2-1/8-24/8}}}

{{{2(x+1/4)^2-25/8}}}

That's in the form {{{a(x+b)^2 + c}}}, a=2, b=1/4, c=-25/8

Edwin</pre>