Paper 1MA1: 3H Question Working Answer Mark 18 Note P1 Recognises that or is 90° or right angle DOC=DOA, OAD OCD 21.6 P1 for trigonometry to set up an equation in or ADO=CDO DOA ADO eg Cos = DOA P1 for using inverse trigonometry to find or DOA ADO eg = Cos-1 (= 56.25…) DOA P1 for a complete process to find arc length or ABC AC eg ×2××5 (=21.598..) or ×2××5 (=9.8174..) A1 for answer in the 21.5 to 21.65 19 M1 for a step to solve the quadratic e.g. factorisation: or or using the formula A1 for and −2 A1 20 (a) (0,1) B1 (0,1) (b) Circle radius 4 M1 For centre (3,0) implied by drawing or label Centre (3,0) and or a circle of radius 4 (1,0) and (7,0) or intersections on the at 7 implied by drawing or labels x-axis −1or labelled M1 for 2 of centre (3,0) implied by drawing or label intersections on the at and 7 implied by drawing or label x-axis −1 circle with radius 4 A1 for a fully correct answer
Paper 1MA1: 3H Question Working Answer Mark 18 Note DOC=DOA, 21.6 P1 Recognises that OAD or OCD is 90° or right angle ADO=CDO P1 for trigonometry to set up an equation in DOA or ADO eg Cos DOA = P1 for using inverse trigonometry to find DOA or ADO eg DOA = Cos-1 (= 56.25…) P1 for a complete process to find arc length ABC or AC eg ×2××5 (=21.598..) or ×2××5 (=9.8174..) A1 for answer in the 21.5 to 21.65 19 M1 for a step to solve the quadratic e.g. factorisation: or or using the formula A1 for −2 and A1 20 (a) (0,1) B1 (0,1) (b) Circle radius 4 Centre (3,0) and (1,0) and (7,0) labelled M1 For centre (3,0) implied by drawing or label or a circle of radius 4 or intersections on the x-axis at −1or 7 implied by drawing or labels M1 for 2 of centre (3,0) implied by drawing or label intersections on the x-axis at −1 and 7 implied by drawing or label circle with radius 4 A1 for a fully correct answer
1ma1_3h_-_june_2017_mark_scheme.docx