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Agile Algebra

Observe symmetries and engage the power of substitution to solve complicated equations.

Graphs of Changing Areas

Use graphs to gain insights into an area and perimeter problem, or use your knowledge of area and perimeter to gain insights into the graphs...

Complex Partial Fractions

Age 16 to 18 Challenge Level:
Just use the usual methods for partial fractions and factorise $x^2+1$ into $(x+i)(x-i)$.