Q1
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M17/5/MATHL/HP1/ENG/TZ1/XX/7 |
Question Text | An arithmetic sequence has and common difference .
(a) Given that and are the first three terms of a geometric sequence, find the value of ; |
Total Mark | 4 |
Correct Answer | 2 |
Explanation | n/a |
Mark Scheme | Step 1: Consider the given information
Given information are , and that and form a geometric sequence.
Step 2: Combine the given information
Step 3: We haven’t used the geometric sequence yet so,
We can notice that,
Replacing the current variables what we determined in step 2,
Expand and simplify
So, |
Question Text | (b) Given that , where n is a positive integer, determine the value of . |
Total Mark | 3 |
Correct Answer | 88 |
Explanation | n/a |
Mark Scheme | Step 1: Point out the given information, from part (a), and
Step 2: Combine the given information to find useful information
so
Step 3: Refer back to the question: determine the value of
of the first 11 terms of the arithemtic sequence, given by the formula,
Answer: 88 |
Q2
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M17/5/MATHL/HP1/ENG/TZ2/XX/3 |
Question Text | The 1st, 3rd, and 6th terms of an arithmetic sequence, with common difference , are the first three terms of a geometric sequence, with common ratio r. Given that the 1st term of both sequences is 4.
(a) Find the value of . |
Total Mark | 4 |
Correct Answer | 1 |
Explanation | n/a |
Mark Scheme | Step 1: Consider the given information.
Given information are and and that and from a geometric sequence.
Step 2: Combine the given information.
If we use the information that the 1st, 3rd, and 6th terms of the arithmetic sequence form a geometric sequence,
Then, we can attempt to find the value of .
Expand and simplify.
Since
Answer = 1 |
Question Text | (b) Find the value of . |
Total Mark | 1 |
Correct Answer | 3 |
Explanation | n/a |
Mark Scheme | Step 1: Point out the given information,
Step 2: Combine the given information.
Use the value of d to find the first two terms of the geometric sequence.
Hence, we can find by using ratios.
Hence, |
Q3
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | N16-TZ0-P1-6(HL) |
Question Text | The sum of the first n terms of a sequence is given by , where .
(a) Write down the value of . |
Total Mark | 1 |
Correct Answer | 1 |
Explanation | n/a |
Mark Scheme | |
Question Text | (b) Find the value of . |
Total Mark | 2 |
Correct Answer | 47 |
Explanation | n/a |
Mark Scheme |
Answer: 47 |
Question Text | (c) Given that {uₙ} is an arithmetic sequence, clearly state its common difference. |
Total Mark | 4 |
Correct Answer | 8 |
Explanation | n/a |
Mark Scheme | Step 1: Consider the given information and identify what we need to prove.
If we assume
un to be an arithmetic sequence, we can find the expression for the arithmetic sequence by using the following expression.
Step 2: Combine the given information.
Substitute the sum of the arithmetic sequence expression into and .
Now, we can find the common difference using the arithmetic sequence.
|
Q4
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M16-TZ1-P1-1(HL) |
Question Text | The seventh term of an arithmetic sequence is equal to 3 and the sum of the first 16 terms is 24.
(a) Find the common difference. |
Total Mark | 3 |
Correct Answer | -1 |
Explanation | n/a |
Mark Scheme | Step 1: Consider the given information.
We know that the 7th term of the arithmetic sequence is 3 and the sum of the first 16 terms is 24.
Step 2: Combine the given information.
We can combine the two equations by expressing u₁ in terms of .
Answer: -1 |
Question Text | (b) Find the first term. |
Total Mark | 3 |
Correct Answer | 9 |
Explanation | n/a |
Mark Scheme | Now, we can use the value of to find the first term.
Answer: 9 |
Q5
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M15-TZ1-P1-12(HL) |
Question Text | Let , be an arithmetic sequence with first term equal to and common difference of , where . Let another sequence , be defined by .
(a)
(i) Given that is a constant and can be expressed in terms , find the value of .
Total Mark: 2
Correct Answer: 2
Explanation: n/a
Mark Scheme:
(ii) Write down the first term of the sequence .
(a)
(b)
(c)
(d)
Total Mark: 1
Correct Answer: (b)
Explanation: n/a
Mark Scheme: x
(iii) Write down a formula for in terms of a, d and n.
(a)
(b)
(c)
(d)
Total Mark: 1
Correct Answer: (d)
Explanation: n/a
Mark Scheme: x
|
Question Text | (b) Let {Sₙ} be the sum of the first n terms of the sequence {vₙ}.
(i) Find {Sₙ}, in terms of a, d and n.
(a)
(b)
(c)
(d)
Total Mark: 1
Correct Answer: (d)
Explanation: n/a
Mark Scheme: x
(ii) Find range of d for which exists.
(a)
(b)
(c)
(d)
Total Mark: 3
Correct Answer: (c)
Explanation: n/a
Mark Scheme:
For the sum of infinity to exist, the following condition must be satisfied.
(iii) You are now told that does exist and is denoted by .
(a)
(b)
(c)
(d)
Total Mark: 1
Correct Answer: (d)
Explanation: n/a
Mark Scheme:
Substitute u₁ and r into S∞ equation, as |r| is given to be less than 1.
(iv) Given that find the value of .
Total Mark: 3
Correct Answer: -3
Explanation: n/a
Mark Scheme:
Utilize your answer from (iii) and substitute it into the equation.
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Q6
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M15-TZ1-P1-12(HL) |
Question Text | Let , be a geometric sequence with first term equal to p and common ratio , where and are both greater than zero. Let another sequence be defined by . Find , giving your answer in the form with in terms of and .
(a)
(b)
(c)
(d) |
Total Mark | 6 |
Correct Answer | (d) |
Explanation | n/a |
Mark Scheme | We can express in terms of and .
Using this expression, we can find the first term and common difference of the {} sequence.
Hence, {} is an arithmetic sequence with the first term being and the common difference being
Finally, we can find the sum of the arithmetic sequence as below.
or
Answer: (d) |
Q7
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M14/5/MATHL/HP1/ENG/TZ1/X/13 |
Question Text | A geometric sequence , with complex terms, is defined by .
(a) Find the fourth term of the sequence, giving your answer in the form . |
Total Mark | 2 |
Correct Answer | |
Explanation | n/a |
Mark Scheme | METHOD 1
Solve the fourth term by following through the sequence.
METHOD 2
Calculate the fourth term by understanding the pattern.
Answer: |
Question Text | (b) Find the sum of the first 20 terms of . Giving your answer in the form , find the sum of and . |
Total Mark | 3 |
Correct Answer | 14 |
Explanation | n/a |
Mark Scheme | Use the summation formula for geometric sequences (formula booklet)
Answer: 14 |
Question Text | (c) Given that is a geometric sequence, its first term can be expressed as Find the value of . |
Total Mark | 2 |
Correct Answer | 16 |
Explanation | n/a |
Mark Scheme | Rearrange the expression for
to find the general formula of the geometric sequence.
Hence, the value of p is 16.
Answer: 16 |
Question Text | A third sequence is defined by .
(d) Given that forms a geometric sequence with a common ratio of √k, state the value of .
(a)
(b)
(c)
(d) |
Total Mark | 4 |
Correct Answer | (d) |
Explanation | n/a |
Mark Scheme | Find the general formula of the geometric sequence.
Answer: (d) |
Q8
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M14/5/MATHL/HP1/ENG/TZ2/XX/9 |
Question Text | The first three terms of a geometric sequence are , and
(a) Find the common ratio . |
Total Mark | 2 |
Correct Answer | |
Explanation | n/a |
Mark Scheme | To find the common ratio of the geometric sequence, we can divide the second term by the first term.
|
Question Text | (b) Find the set of values of x for which the geometric series converges.
(a)
(b)
(c)
(d) |
Total Mark | 4 |
Correct Answer | (a) |
Explanation | n/a |
Mark Scheme | For the geometric series to converge, the absolute value of the common ratio should be smaller than 1.|r|<1
or
then
Answer: (a) |
Question Text | (c) Given that the sum to infinity of this series is , find the value of . |
Total Mark | 4 |
Correct Answer | 2 |
Explanation | n/a |
Mark Scheme | Use the sum of infinite geometric series formula to find the value of
Hence, the value of is equal to 2.
Answer: 2 |
Q9
Topic | 1.2 Numbers and Algebra | |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance | |
Source | N13-TZ0-P1-7(HL) | |
Question Text | The sum of the first two terms of a geometric series is 20 and the sum of the first four terms is 40.
(a) Find the value of . | |
Total Mark | 4 | |
Correct Answer | 4 | |
Explanation | n/a | |
Mark Scheme | Step 1: Consider the given information.
The question has provided us the sum of the first two terms and sum of the first tour terms. We can express the given information as an equation.
Stop 2: Combine the given information.
We can combine the two equation to find the value of .
Answer: 4 | |
Question Text | (b) Given
(i) the first term will be in the form . Find .
Total Mark: 1
Correct Answer: 10
Explanation: n/a
Mark Scheme:
To find the first term, we need to find the value of
a using the given value.
Answer: 10
(ii) find the sum of the first ten terms.
Total Mark: 2
Correct Answer: 3410
Explanation: n/a
Mark Scheme:
We can use the sum of geometric series to find the value of .
Answer: 3410 |
Q10
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M13-TZ1-P1-8(HL) |
Question Text | The first terms of an arithmetic sequence are
Find if the sum of the 20 terms of the sequence is equal to 100. |
Total Mark | 6 |
Correct Answer | 27 |
Explanation | n/a |
Mark Scheme | Tip 1: Find the common difference of the arithmetic sequence.
Tip 2: Find the value of by using the given information that the sum of the first 12 terms is equal to 48.
The sum of the first 12 terms in the arithmetic sequence can be found by using the following formula.
Hence, we can find .
Answer: 27 |
Q11
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M13-TZ2-P1-6(HL) |
Question Text | A geometric sequence has first term , common ratio r and sum to infinity 36.
A second geometric sequence has first term , common ratio and sum to infinity 16.
Given that the value of can be expressed as find the value of . |
Total Mark | 7 |
Correct Answer | 26 |
Explanation | n/a |
Mark Scheme | Step 1: Consider the given information.
We can express the first series as
and the second series as
Step 2: Combine the given information.
To solve for the value of , we can attempt eliminate by using the substitution method.
Simplify and obtain
Hence, the value of is equal to .
Answer: 6 |
Q12
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M19/5/MATHL/HP1/ENG/TZ2/XX/1 |
Question Text | In an arithmetic sequence, the sum of the 4th and 6th term is -2. Given that the sum of the first eight terms is 8, determine the sum of the first term and the common difference. |
Total Mark | 1 |
Correct Answer | 11 |
Explanation | n/a |
Mark Scheme | Attempt to from two equation involving the first term and the common difference to find their values.
(1)
(2)
Hence, the first term and common difference can be determined as the following
The sum of the two terms is equal to 11.
Answer: 11 |
Q13
Topic | 1.2 Numbers and Algebra |
Tag | Sequences; Series; Arithmetic; Geometric; Sigma; Compound interest; Finance |
Source | M18/5/MATHL/HP1/ENG/TZ2/XX/5 |
Question Text | The geometric sequence has a common ratio . Consider the sequence
(a) Given that is an arithmetic sequence, state its common difference in terms of .
(a)
(b)
(c)
(d) |
Total Mark | 4 |
Correct Answer | (a) |
Explanation | n/a |
Mark Scheme | Tip 1: Find an expression for the common difference .
Using the given information, the arithmetic sequence’s common difference can be expressed as
Tip 2: Use the information that is a geometric sequence.
Since we know that is a geometric sequence, we can express the common difference in terms of .
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Question Text | (b) Find the value of . |
Total Mark | 3 |
Correct Answer | -1 |
Explanation | n/a |
Mark Scheme | We are given the information that the sum to infinity of the geometric sequence is equal to 4.
Answer: -1
|