Expanding and factorising quadratics

There are 38 NRICH Mathematical resources connected to Expanding and factorising quadratics
Spot the difference
problem

Spot the difference

Age
16 to 18
Challenge level
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If you plot these graphs they may look the same, but are they?
Leftovers
problem

Leftovers

Age
14 to 16
Challenge level
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Weekly Problem 26 - 2008
If $n$ is a positive integer, how many different values for the remainder are obtained when $n^2$ is divided by $n+4$?
Spinners
problem

Spinners

Age
16 to 18
Challenge level
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How do scores on dice and factors of polynomials relate to each other?
Polar Flower
problem

Polar Flower

Age
16 to 18
Challenge level
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This polar equation is a quadratic. Plot the graph given by each factor to draw the flower.
Perfectly Square
problem

Perfectly Square

Age
14 to 16
Challenge level
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The sums of the squares of three related numbers is also a perfect square - can you explain why?
Pair Products
problem

Pair Products

Age
14 to 16
Challenge level
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Choose four consecutive whole numbers. Multiply the first and last numbers together. Multiply the middle pair together. What do you notice?
Multiplication Magic
problem

Multiplication Magic

Age
14 to 16
Challenge level
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Given any 3 digit number you can use the given digits and name another number which is divisible by 37 (e.g. given 628 you say 628371 is divisible by 37 because you know that 6+3 = 2+7 = 8+1 = 9). The question asks you to explain the trick.
Poly Fibs
problem

Poly Fibs

Age
16 to 18
Challenge level
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A sequence of polynomials starts 0, 1 and each poly is given by combining the two polys in the sequence just before it. Investigate and prove results about the roots of the polys.
Fibonacci Factors
problem

Fibonacci Factors

Age
16 to 18
Challenge level
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For which values of n is the Fibonacci number fn even? Which Fibonnaci numbers are divisible by 3?
Composite Notions
problem

Composite Notions

Age
14 to 16
Challenge level
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A composite number is one that is neither prime nor 1. Show that 10201 is composite in any base.