Hint
Use the stated units and precision. Translate the expression into disjoint regions and add each required region once.
Worked solution
(a)
Translate the expression into disjoint regions and add each required region once.
\(21\)
Answer: \(21\)
(b)
Translate the expression into disjoint regions and add each required region once.
\(7\)
Answer: \(7\)
(c)
Translate the expression into disjoint regions and add each required region once.
\(4\)
Answer: \(4\)
Maths4U indicative marking guidance
Maths4U indicative marking guidance, not an official mark scheme. Credit complete valid alternative methods and consequential reasoning. An unexplained result does not earn a method mark.
(a) · 2 marks
- 1 mark: Translate the expression into disjoint regions and add each required region once.
- 1 mark: Give the correct requested result, retaining signs, units and any domain restrictions.
Alternative methods: Any complete mathematically valid alternative method with the same restrictions and equivalent exact result is acceptable.
Common error: Keep intermediate values exact until the final step.
(b) · 2 marks
- 1 mark: Translate the expression into disjoint regions and add each required region once.
- 1 mark: Give the correct requested result, retaining signs, units and any domain restrictions.
Alternative methods: Any complete mathematically valid alternative method with the same restrictions and equivalent exact result is acceptable.
Common error: Check the answer against the original conditions.
(c) · 2 marks
- 1 mark: Translate the expression into disjoint regions and add each required region once.
- 1 mark: Give the correct requested result, retaining signs, units and any domain restrictions.
Alternative methods: Any complete mathematically valid alternative method with the same restrictions and equivalent exact result is acceptable.
Common error: Keep intermediate values exact until the final step.
Total: 6 marks.