Reflections

There are 58 NRICH Mathematical resources connected to Reflections
Simplifying Transformations
problem

Simplifying Transformations

Age
11 to 14
Challenge level
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How many different transformations can you find made up from combinations of R, S and their inverses? Can you be sure that you have found them all?
Combining Transformations
problem

Combining Transformations

Age
11 to 14
Challenge level
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Does changing the order of transformations always/sometimes/never produce the same transformation?
Decoding Transformations
problem

Decoding Transformations

Age
11 to 14
Challenge level
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See the effects of some combined transformations on a shape. Can you describe what the individual transformations do?
Rotations Are Not Single Round Here
problem

Rotations Are Not Single Round Here

Age
14 to 16
Challenge level
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I noticed this about streamers that have rotation symmetry : if there was one centre of rotation there always seems to be a second centre that also worked. Can you find a design that has only one centre of rotation ? Or if you thought that was impossible, could you say why ?
One Reflection Implies Another
problem

One Reflection Implies Another

Age
14 to 16
Challenge level
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When a strip has vertical symmetry there always seems to be a second place where a mirror line could go. Perhaps you can find a design that has only one mirror line across it. Or, if you thought that was impossible, could you explain why ?
A Roll Of Patterned Paper
problem

A Roll Of Patterned Paper

Age
14 to 16
Challenge level
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A design is repeated endlessly along a line - rather like a stream of paper coming off a roll. Make a strip that matches itself after rotation, or after reflection
Footprints
problem

Footprints

Age
16 to 18
Challenge level
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Make a footprint pattern using only reflections.
Orbiting Billiard Balls
problem

Orbiting Billiard Balls

Age
14 to 16
Challenge level
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What angle is needed for a ball to do a circuit of the billiard table and then pass through its original position?
Patchwork Quilt
problem

Patchwork Quilt

Age
7 to 14
Challenge level
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Squares of the type shown are sewn together to make a quilt. How many different quilts can be made?
Screen Shot
problem

Screen Shot

Age
14 to 16
Challenge level
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A moveable screen slides along a mirrored corridor towards a centrally placed light source. A ray of light from that source is directed towards a wall of the corridor, which it strikes at 45 degrees before being reflected across to the opposite wall and so on until it hits the screen.