2. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
3. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
4. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
2S n a l a l a l a l a l a l
5. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
2S n a l a l a l a l a l a l
na l
6. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
2S n a l a l a l a l a l a l
na l
n
S n a l if we know l
2
7. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
2S n a l a l a l a l a l a l
na l
n
S n a l if we know l
2
otherwise;
8. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
2S n a l a l a l a l a l a l
na l
n
S n a l if we know l
2
otherwise;
n
S n a a n 1d
2
9. Sum Of An Arithmetic
Series
S n a a d a 2d l 2d l d l
S n l l d l 2d a 2 d a d a
2S n a l a l a l a l a l a l
na l
n
S n a l if we know l
2
otherwise;
n
S n a a n 1d
2
n
S n 2a n 1d
2
11. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
12. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
13. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
297
14. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
297
ii Find the sum of the first 100 even numbers
15. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
297
ii Find the sum of the first 100 even numbers
a 2, d 2 and n 100
16. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
297
ii Find the sum of the first 100 even numbers
a 2, d 2 and n 100
n
S n 2a n 1d
2
17. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
297
ii Find the sum of the first 100 even numbers
a 2, d 2 and n 100
n
S n 2a n 1d
2
100
S100 4 992
2
18. e.g. i If a 3 and T6 96, find S6
n
S n a l
2
6
S6 3 96
2
297
ii Find the sum of the first 100 even numbers
a 2, d 2 and n 100
n
S n 2a n 1d
2
100
S100 4 992
2
50 202
10100
19. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
20. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100
21. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100
10
2a 9d 100
2
22. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100
10
2a 9d 100
2
2a 9d 20
23. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10
2a 9d 100
2
2a 9d 20
24. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20
25. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
26. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
2a 9d 20
2a 4d 10
27. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
2a 9d 20
2a 4d 10
5d 10
28. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
2a 9d 20
2a 4d 10
5d 10
d 2 a 1
29. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
2a 9d 20
2a 4d 10
5d 10
d 2 a 1
Tn a n 1d
30. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
2a 9d 20
2a 4d 10
5d 10
d 2 a 1
Tn a n 1d
1 n 12
2n 1
31. iii The sum of the first 10 numbers is 100 and the first 5 numbers is 25.
Find a, d and the general term.
S10 100 S5 25
10 5
2a 9d 100 2a 4d 25
2 2
2a 9d 20 a 2d 5
2a 9d 20
2a 4d 10
5d 10
d 2 a 1
Tn a n 1d
1 n 12
2n 1 a 1, d 2, Tn 2n 1