Time: 1 hour total marks 7 list of formuls por the qusdratic equatio ac-o the number of real roits of she sollowing espmessioess (a) x5x5 (b) x +a + 1 (e) x 10 show that the oquation 3.5+525-0 does ot have any real roots l2) (b) find the values of k for which the equation -6xk -0has a repeated root 12) byfirst expressingx2-5x+8in the form (x+吖+b writedown the coordraes of the minimum point of the curve with equation y-5x8 3 (a) 13) (b) sketch the curve, showing on your sketch the line of symmetry, the coordinates of the 31 minimum point and where the curve mects the y axis