I want to know how to solve it.
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Answer:
f(1+g(1))=2 is your answer
Explanation:
we have
f(x)={2x-2}/(x²+1)
g(x)=x²+1
now
f(1+g(1))=f(1+(1²+1))=f(1+2)=f(3)={2×3-2}/(1²+1)=4/2=2