change of sign
What change of sign means in Mathematics A-Level, as defined for Pearson Edexcel, WJEC.
Definitions of change of sign
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Reference: WJEC
Opposite signs of f(a) and f(b), expressed by f(a)f(b)<0, indicating at least one root in (a,b) when the function is continuous or sufficiently well-behaved.
A change from a positive function value to a negative one, or from negative to positive, between two inputs.
Topics that use change of sign
- Numerical methods (Pearson Edexcel A-Level)
- Overarching themes - Mathematical problem solving (WJEC A-Level)
Related terms
- Concave up
- Convergence
- Fixed point
- Iteration
- Newton-Raphson method
- Trapezium rule
- accuracy and rounding
- algebraic modelling
Using change of sign in the exam
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