Answer:
f(g(x)) = -1
Step-by-step explanation:


This can be considered as a very easy Question where you have to find the value of √85 and √86 upto 2 decimal places then we could find it easily.
Let's start!
Value of √85=9.21
Value of √86=9.27
Now it is obvious that 9.25 lies between √85 and √86.

What are rational no.?
Any pair of numbers which is in the form of p/q where p and q are integers and p and q are co-prime is called rational number.
Hey!
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Steps To Solve:
~Substitute
(4)2 - (-5)2
~Multiply
8 - (-10)
~Subtract
18
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Answer:
18
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Hope This Helped! Good Luck!