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Complex Partial Fractions

To break down an algebraic fraction into partial fractions in which all the denominators are linear and all the numerators are constants you sometimes need complex numbers.

Agile Algebra

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

Graphs of Changing Areas

Age 16 to 18 Challenge Level:

How does the rectangle with length $x$ and width $y$ relate to the rectangle with width $x$ and length $y$?