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# Need help with Maths question - Mappings watch

1. The following mappings m and n are defined by,

m:x -> 2x + 4 and n:x -> x^2 + 1

find,

a) the function mn(x)
b)the function nm(x)
c)m^2(x)
d) the values of c such that m(c) = n(c)

anyone have any idea as to how I go about doing these?
2. (Original post by HarrisxK)
The following mappings m and n are defined by,

m:x -> 2x + 4 and n:x -> x^2 + 1

find,

a) the function mn(x)
b)the function nm(x)
c)m^2(x)
d) the values of c such that m(c) = n(c)

anyone have any idea as to how I go about doing these?
You're basically dealing with a function of a function for the first three.

mn(x) can be written as m(n(x)). You know n(x) is x^2+1, so m(n(x)) becomes m(x^2+1).

Can you take it from there?

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Updated: September 22, 2014
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