4x^2 + 8x + 3 can be written in the form a(x + b)^2 + c where a, b and c are whole numbers. Work out the values of a, b and c.
Factorise 4x2 + 8x + 3 = 4(x2 + 2x + 3/4) divide the coefficient of x by 2: 2/2=1 Now x2+2x = (x+1)2-12 = (x+1)2-1 Hence, 4((x+1)2-1+3/4) = 4(x+1)2-1 which is of the form a(x + b)2 + c So a=4, b=1, c=-1
DW
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