So or equivalent A1 (2) (b) Determinant: M1A1 (2) (c) (4) [8] Question Scheme Marks Number 7. (a) M1 A1 (*) M1 A1 (4) (b) only B1 (1) (c) so M1 A1cso = M1 A1 cso (4) (d) Line has gradient PQ M1 A1 has gradient or could be as unsimplified ON equivalents seen anywhere B1 As these lines are perpendicular so OR for ON with gradient (equivalent to) and sub in points to give pq O N OR for PQ with gradient (equivalent to) and sub in points to give P Q –pq M1 A1 (5)
So or equivalent A1 (2) (b) Determinant: M1A1 (2) (c) (4) [8] Question Number Scheme Marks 7. (a) M1 A1 (*) M1 A1 (4) (b) only B1 (1) (c) so M1 A1cso = M1 A1 cso (4) (d) Line PQ has gradient M1 A1 ON has gradient or could be as unsimplified equivalents seen anywhere B1 As these lines are perpendicular so OR for ON with gradient (equivalent to) pq and sub in points O N to give OR for PQ with gradient (equivalent to) –pq and sub in points P Q to give M1 A1 (5)