Arithmetic Series www mathsrevision com Adv Higher nth

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Arithmetic Series www. mathsrevision. com Adv. Higher nth term & Sum of Arithmetic Series

Arithmetic Series www. mathsrevision. com Adv. Higher nth term & Sum of Arithmetic Series nth and sum of Geometric Series Maclaurin’s Expansion 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series An Arithmetic Series is a sequence which differs by the same amount

Arithmetic Series An Arithmetic Series is a sequence which differs by the same amount each time Let the first term be a and the difference be d then 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Example : Find a formula for the nth term of the sequence

Arithmetic Series Example : Find a formula for the nth term of the sequence 9, 12, 15, . . . and the 20 th term. a=9 d = 12 - 9 = 3 u 20 = 3(20) + 6 un = a + (n – 1)d u 20 = 60 + 6 un = 9 + 3(n – 1) u 20 = 66 un = 3 n + 6 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series The sum of an Arithmetic Series Rewriting the terms in reverse Now

Arithmetic Series The sum of an Arithmetic Series Rewriting the terms in reverse Now adding each corresponding terms 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series For a infinite number of terms then a = first term l

Arithmetic Series For a infinite number of terms then a = first term l = last term 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Example : For 2 + 5 + 8 + 11 +. .

Arithmetic Series Example : For 2 + 5 + 8 + 11 +. . . Find u 15 and S 8. a=2 d=3 un = 2 + 3(n – 1) un = 3 n – 1 S 8 = 100 u 15 = 3(15) - 1 = 44 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Example : If the first term is 37 and difference is -4.

Arithmetic Series Example : If the first term is 37 and difference is -4. Find u 15 and S 8. un = a + (n – 1)d u 15 = 37 - 4(15 – 1) u 15 = -19 29 -Jan-22 S 8 = 184 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Example : Find the number of terms in the series 5 +

Arithmetic Series Example : Find the number of terms in the series 5 + 8 + 11. . . + 62. a=5 d=3 un = a + (n – 1)d 5 + 3(n – 1) = 62 3 n + 2 = 62 n = 20 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Example : Find the sum of 2 + 4 + 6 +

Arithmetic Series Example : Find the sum of 2 + 4 + 6 + 8. . + 146 a=2 d=2 un = a + (n – 1)d 2 + 2(n – 1) = 146 2 n = 146 n = 73 29 -Jan-22 S 8 = 5402 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Example : The second term of an Arith. sequence is 18 and

Arithmetic Series Example : The second term of an Arith. sequence is 18 and fifth is 21. Find the common difference, first term and sum of the first 10 terms un = a + (n – 1)d (u 2) a + d = 18 (u 5) a + 4 d = 21 d=1 a = 17 29 -Jan-22 S 10 = 215 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Exercise 1 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Exercise 1 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Geometric Series A Geometric sequence is one in which the ratio of each term

Geometric Series A Geometric sequence is one in which the ratio of each term to the previous is a constant called the common ratio (r) 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Sum of Geometric Series Let Sn denote the sum of n terms, a the

Sum of Geometric Series Let Sn denote the sum of n terms, a the first term and r the common ratio. If r > 1 better to use 29 -Jan-22 Created by Mr. Lafferty Maths Dept. r≠ 1

Sum of Geometric Series Find u 10 for the Geometric Sequence : - 144,

Sum of Geometric Series Find u 10 for the Geometric Sequence : - 144, 108, 81, 60¾ 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Sum of Geometric Series Find S 19 for the Geometric Sequence : - 3,

Sum of Geometric Series Find S 19 for the Geometric Sequence : - 3, -6, 12, -24. . . 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Sum of Geometric Series A Geometric Series has the first term 27 and common

Sum of Geometric Series A Geometric Series has the first term 27 and common ratio Take logs Find the least number of terms the series can have if its sum exceeds 550. 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Sum of Geometric Series A Geometric Series has the first term 27 and common

Sum of Geometric Series A Geometric Series has the first term 27 and common ratio Take logs Find the least number of terms the series can have if its sum exceeds 550. 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Sum of Geometric Series Given find Sub into 29 -Jan-22 Created by Mr. Lafferty

Sum of Geometric Series Given find Sub into 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Exercise 2 A 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Exercise 2 A 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Maclaurin’s Theorem Expansions You need to learn the basic expansions 29 -Jan-22 Created by

Maclaurin’s Theorem Expansions You need to learn the basic expansions 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Maclaurin’s Theorem Expansions We can combine expansions to more complicated functions. Expand 29 -Jan-22

Maclaurin’s Theorem Expansions We can combine expansions to more complicated functions. Expand 29 -Jan-22 up to the power of x 4 Created by Mr. Lafferty Maths Dept.

Maclaurin’s Theorem Expansions Expand up to the power of x 4 etc. . .

Maclaurin’s Theorem Expansions Expand up to the power of x 4 etc. . . 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Trick ! Maclaurin’s Theorem ( 1 + cosx - 1 ) Expansions Expand up

Trick ! Maclaurin’s Theorem ( 1 + cosx - 1 ) Expansions Expand up to the power of x 6 But Now sub into ln(1 + x) 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Maclaurin’s Theorem Expansions Expand 29 -Jan-22 up to the power of x 6 Created

Maclaurin’s Theorem Expansions Expand 29 -Jan-22 up to the power of x 6 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Exercise 2 29 -Jan-22 Created by Mr. Lafferty Maths Dept.

Arithmetic Series Exercise 2 29 -Jan-22 Created by Mr. Lafferty Maths Dept.