domain restrictions
What domain restrictions means in Mathematics A-Level, as defined for WJEC.
Definitions of domain restrictions
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Reference: WJEC
Conditions such as u > 0 for u = eˣ, u ≥ 0 for u = √x and −1 ≤ u ≤ 1 for trigonometric substitutions, rejecting invalid branches.
Its domain is restricted to strictly positive real numbers, {x ∈ ℝ : x > 0}, and its range is all real numbers ℝ.
Practical domain limits based on physical constraints, such as time or height not taking negative values.
Topics that use domain restrictions
- Algebra and Functions (A2 Unit 3: Pure Mathematics B) (WJEC A-Level)
- Algebra and Functions (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
- Exponentials and logarithms (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
Related terms
- algebraic division
- inverse functions
- reflection in y = x
- ambient temperature baseline
- Asymptotes
- boundary curves
- cancelling factors
- carrying capacity
Using domain restrictions in the exam
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