6 7.18cm 4 P1 starts process eg. Pythagoras theorem for 271.4 seen P1 for subtracting radius from their answer P1 cao A1 7 (a) 1 B1 cao or 0.125 (b) for 2 M1 cao A1 8 3 M1 for oe for or M1 cao A1 9 4 for Proof shown M1 for M1 for M1 cao C1 10 3 M1 for 2nd difference is 4 First difference 8, 12, 16, 20 M1 for 2nd difference 4. hence A1 cao -3 -1 1 3 th term is
6 7.18cm 4 P1 P1 P1 A1 starts process eg. Pythagoras theorem for 271.4 seen for subtracting radius from their answer cao 7 (a) (b) or 0.125 1 2 B1 M1 A1 cao for cao 8 oe 3 M1 M1 A1 for for or cao 9 Proof shown 4 M1 M1 M1 C1 for for for cao 10 First difference 8, 12, 16, 20 2nd difference 4. hence -3 -1 1 3 th term is 3 M1 M1 A1 for 2nd difference is 4 for cao