How do you factorise a quadratic expression using the formula
To factorise an expression of the formax2+bx+c We use the formulaX=(-b+/- (b^2-4ac)^(1/2))/2aExample:Factorise 3X2+2X+-1So here a=3 b=2 c=-1From the formula we get X=1/3 and X=-1And so our factorisation is (X-1/3)(X+1)
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