Question 316747
a) 2*2^2(a+b)c^2 / 16[(a+b)c]^2

8(a+b)^2 c^2 / 16(a+b)^2*c^2
=8/16
=1/2

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and 
b) (x^2 - y^2) / (x+y) +y

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x^2-y^2 / x+y   + y

x^2-y^2 + y(x+y) / x+y
x^2-y^2+xy+y^2 / x+y
x^2+xy / (x+y)
x(x+y) / (x+y)
=x

Cheers Nick