Complex numbers

There are 22 NRICH Mathematical resources connected to Complex numbers
Sheep in wolf's clothing
problem

Sheep in wolf's clothing

Age
16 to 18
Challenge level
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Can you work out what simple structures have been dressed up in these advanced mathematical representations?
Impedance can be complex!
problem

Impedance can be complex!

Age
16 to 18
Challenge level
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Put your complex numbers and calculus to the test with this impedance calculation.
Pumping the Power
problem

Pumping the Power

Age
16 to 18
Challenge level
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What is an AC voltage? How much power does an AC power source supply?
Sextet
problem

Sextet

Age
16 to 18
Challenge level
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Investigate x to the power n plus 1 over x to the power n when x plus 1 over x equals 1.
Footprints
problem

Footprints

Age
16 to 18
Challenge level
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Make a footprint pattern using only reflections.
Complex partial fractions
problem

Complex partial fractions

Age
16 to 18
Challenge level
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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.
Complex Sine
problem

Complex Sine

Age
16 to 18
Challenge level
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Solve the equation sin z = 2 for complex z. You only need the formula you are given for sin z in terms of the exponential function, and to solve a quadratic equation and use the logarithmic function.
Thousand Words
problem

Thousand Words

Age
16 to 18
Challenge level
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Here the diagram says it all. Can you find the diagram?
Three by One
problem

Three by One

Age
16 to 18
Challenge level
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There are many different methods to solve this geometrical problem - how many can you find?