Mixed Topic Worksheet Grades 8/9: Day 093
- 1
Question 1. Write √726 in the form a√b where a and b are integers and b is as small as possible.
Simplifying Surds▶ Show worked answerHide worked answer
- M1: √121 × 6
- A1: 11√6
Answer: 11√6[2 marks] - 2
Question 2. Write dfrac2x+1+dfrac3x+4 as a single fraction.
Give your answer in the form dfracax+b(x+1)(x+4).Algebraic Fractions Involving Factorising▶ Show worked answerHide worked answer
- M1: common denominator (x+1)(x+4)
- M1: 2(x+4)+3(x+1)
- A1: dfrac5x+11(x+1)(x+4)
Answer: dfrac5x+11(x+1)(x+4)[3 marks] - 3
Question 3. y is directly proportional to the cube of x and inversely proportional to z.
x is decreased by 10%.
The value of y does not change.
Work out the percentage change in z.Direct & Inverse Proportion with Functions▶ Show worked answerHide worked answer
- M1: y = dfrackx³z, so z = dfrackx³y for fixed y
- M1: new z is 0.9³ = 0.729 times the old z
- A1: z decreases by 27.1%
Answer: 27.1% decrease[3 marks] - 4
Question 4. n is a positive integer.
Prove that the product of four consecutive integers, plus 1, is a square number.Proof with Consecutive Numbers▶ Show worked answerHide worked answer
- M1: n(n + 3) = n² + 3n and (n + 1)(n + 2) = n² + 3n + 2
- M1: (n² + 3n)(n² + 3n + 2) + 1 = (n² + 3n)² + 2(n² + 3n) + 1
- A1: (n² + 3n + 1)²
- C1: n² + 3n + 1 is an integer, so the result is a square number
Answer: (n² + 3n + 1)²[4 marks] - 5
Question 5. Solve 2x² - 7x - 15 > 0
Solving Quadratic Inequalities▶ Show worked answerHide worked answer
- M1 A1: (2x + 3)(x - 5) = 0 so x = -1.5 or x = 5
- M1: the outer regions (sketch of the parabola)
- A1: x < -1.5 or x > 5
Answer: x < -1.5 or x > 5[4 marks]
Mixed Topic Worksheet Grades 8/9: Day 093
- 1
Question 1. Write √726 in the form a√b where a and b are integers and b is as small as possible.
[2 marks]Simplifying Surds▶ Show worked answerHide worked answer
- M1: √121 × 6
- A1: 11√6
Answer: 11√6 - 2
Question 2. Write dfrac2x+1+dfrac3x+4 as a single fraction.
[3 marks]
Give your answer in the form dfracax+b(x+1)(x+4).Algebraic Fractions Involving Factorising▶ Show worked answerHide worked answer
- M1: common denominator (x+1)(x+4)
- M1: 2(x+4)+3(x+1)
- A1: dfrac5x+11(x+1)(x+4)
Answer: dfrac5x+11(x+1)(x+4) - 3
Question 3. y is directly proportional to the cube of x and inversely proportional to z.
[3 marks]
x is decreased by 10%.
The value of y does not change.
Work out the percentage change in z.Direct & Inverse Proportion with Functions▶ Show worked answerHide worked answer
- M1: y = dfrackx³z, so z = dfrackx³y for fixed y
- M1: new z is 0.9³ = 0.729 times the old z
- A1: z decreases by 27.1%
Answer: 27.1% decrease - 4
Question 4. n is a positive integer.
[4 marks]
Prove that the product of four consecutive integers, plus 1, is a square number.Proof with Consecutive Numbers▶ Show worked answerHide worked answer
- M1: n(n + 3) = n² + 3n and (n + 1)(n + 2) = n² + 3n + 2
- M1: (n² + 3n)(n² + 3n + 2) + 1 = (n² + 3n)² + 2(n² + 3n) + 1
- A1: (n² + 3n + 1)²
- C1: n² + 3n + 1 is an integer, so the result is a square number
Answer: (n² + 3n + 1)² - 5
Question 5. Solve 2x² - 7x - 15 > 0
[4 marks]Solving Quadratic Inequalities▶ Show worked answerHide worked answer
- M1 A1: (2x + 3)(x - 5) = 0 so x = -1.5 or x = 5
- M1: the outer regions (sketch of the parabola)
- A1: x < -1.5 or x > 5
Answer: x < -1.5 or x > 5
Mixed Topic Worksheet Grades 8/9: Day 093
- 1
Question 1. Write √726 in the form a√b where a and b are integers and b is as small as possible.
Simplifying Surds▶ Show worked answerHide worked answer
- M1: √121 × 6
- A1: 11√6
Answer: 11√6[2 marks] - 2
Question 2. Write dfrac2x+1+dfrac3x+4 as a single fraction.
Give your answer in the form dfracax+b(x+1)(x+4).Algebraic Fractions Involving Factorising▶ Show worked answerHide worked answer
- M1: common denominator (x+1)(x+4)
- M1: 2(x+4)+3(x+1)
- A1: dfrac5x+11(x+1)(x+4)
Answer: dfrac5x+11(x+1)(x+4)[3 marks] - 3
Question 3. y is directly proportional to the cube of x and inversely proportional to z.
x is decreased by 10%.
The value of y does not change.
Work out the percentage change in z.Direct & Inverse Proportion with Functions▶ Show worked answerHide worked answer
- M1: y = dfrackx³z, so z = dfrackx³y for fixed y
- M1: new z is 0.9³ = 0.729 times the old z
- A1: z decreases by 27.1%
Answer: 27.1% decrease[3 marks] - 4
Question 4. n is a positive integer.
Prove that the product of four consecutive integers, plus 1, is a square number.Proof with Consecutive Numbers▶ Show worked answerHide worked answer
- M1: n(n + 3) = n² + 3n and (n + 1)(n + 2) = n² + 3n + 2
- M1: (n² + 3n)(n² + 3n + 2) + 1 = (n² + 3n)² + 2(n² + 3n) + 1
- A1: (n² + 3n + 1)²
- C1: n² + 3n + 1 is an integer, so the result is a square number
Answer: (n² + 3n + 1)²[4 marks] - 5
Question 5. Solve 2x² - 7x - 15 > 0
Solving Quadratic Inequalities▶ Show worked answerHide worked answer
- M1 A1: (2x + 3)(x - 5) = 0 so x = -1.5 or x = 5
- M1: the outer regions (sketch of the parabola)
- A1: x < -1.5 or x > 5
Answer: x < -1.5 or x > 5[4 marks]