18 4 M1 for multiplying both by 5 + as a first step m M1 for correctly moving their terms to one side and their other m terms to the other side M1 for factorising A1 for oe 19 38.6 5 P1 process to find e.g. tan 34 = CD, P1 process to find e.g. cos 34 = or = 202 + BD, BD2 “CD”2 P1 uses sine rule to find AD e.g. P1 process to find e.g. sin = DAC, DAC A1 answer in range 38.5 38.6 – 20 (a) 18 1 B1 cao (b) shown 2 C1 for step, e.g. (2x 3)2 + 2 – C1 fully correct chain of reasoning that includes correct expansion of (2x 3)2 –
18 4 M1 for multiplying both by 5 + m as a first step M1 for correctly moving their m terms to one side and their other terms to the other side M1 for factorising A1 for oe 19 38.6 5 P1 process to find CD, e.g. tan 34 = P1 process to find BD, e.g. cos 34 = or BD2 = 202 + “CD”2 P1 uses sine rule to find AD e.g. P1 process to find DAC, e.g. sin DAC = A1 answer in range 38.5 – 38.6 20 (a) 18 1 B1 cao (b) shown 2 C1 for step, e.g. (2x – 3)2 + 2 C1 fully correct chain of reasoning that includes correct expansion of (2x – 3)2
17751_12b_mock_papers_set_1_-_paper_3h_mark_scheme.docx