Let f ( x ) = 15 /x and g ( x ) = 2 x − 5 Find fg(4), gf(-30) and give the expression for gf(x)

Key here is the order of operation.g(4) =2x4 - 5=8-5=3fg(4) = f(3)=15/3=5gf(-30)f(-30)=15/-30=-1/2gf(-30)=g(-1/2)=2x-1/2 -5=-1-5=-6gf(x)f(x)=15/xg(15/x)=2*15/x -5=30/x -5

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Answered by Eddie M. Maths tutor

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