Surds and rationalising
Simplify before combining, and rationalise without changing the value.
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Simplify before combining, and rationalise without changing the value.
Use factorised form to find roots and completed-square form to find the turning point.
Work out f(g(x)) and g(f(x)), keeping brackets around the function you substitute.
Find the inverse of a quadratic on each side of its turning point.
Find the nth term and the sum of the first n terms of an arithmetic sequence.
Match the known information to an area, cosine-rule or sine-rule calculation.
Find gradients and recognise equivalent equations of a line.
Use the derivative for a gradient and the original curve for a point.
Calculate AB and BA for two matrices and compare the results.
Multiply using i² = −1 and divide with a conjugate.
Check when a binomial model applies, then calculate the probability of a given number of successes.
Use constant-acceleration equations with a consistent positive direction.